Bradley biology student takes his research on the road

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The work Richwoods High School grad Ryan Niemeier does would be impressive enough just on its face.

The biology student, now in his junior year at Bradley University, has spent the last three years working with nanofiber materials, trying to create "scaffold" systems to help concentrate the delivery of stem cells to help the body repair itself. It's research that could one day help facilitate repairs to damaged organs and lead to cures for conditions like Parkinson's disease.

And now he's taking the research on the road, with a prestigious nine-month fellowship to Galway, Ireland, to expand his work and come at it from a different perspective and with the advice of different scientists.

Niemeier stands out among students at Bradley, said mentor Craig Cady, a Bradley biology professor whose research is directed in similar areas.

"It's unusual for a student ... to see him advance that much at that age," he said. "Some students are intimidated at that age - a lot of research, a lot of stress. But Ryan was very much at ease. He can make decisions on his own," Cady said.

In fact, though still a student, he's frequently been the one in the driver's seat when it comes to determining where he wants to take his studies.

"Ryan basically was involved in implementing and creating a design to literally do the research" that led him to where he is today, Cady said.

"I've been able to set up and design all my experiments from the ground up," Niemeier said shortly before leaving last month for the Emerald Isle.

And that's precisely what he said he was looking for in choosing a course of study, first at Bradley and then with the fellowship: "Am I going to be able to get into a lab and am I going to be able to do meaningful research?"

The two share a student-mentor relationship, but because of the direction of their research and the amount of time they have spent together since the summer after Niemeier's junior year of high school, Cady said, they can also work as collaborators.

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Bradley biology student takes his research on the road

UCLA Chemist Steven G. Clarke Named to Endowed Chair in Gerontology

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Removing molecular 'garbage' may be key to successful aging, Clarke says

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Newswise Steven G. Clarke, a distinguished professor in the department of chemistry and biochemistry in UCLA's College of Letters and Science, has been named to UCLA's Elizabeth and Thomas Plott Chair in Gerontology.

The endowed chair, held for a five-year term, is intended for a scholar who conducts research and education activities related to aging and longevity in the areas of molecular biology, neuroscience and immunology.

An authority in his field, Clarke focuses on the biochemistry of the aging process and conducts research aimed at understanding, on a molecular level, how human functions are maintained during aging.

His research team has proposed that a major factor in the successful aging of all organisms is how well age-generated molecular "garbage" damaged proteins, nucleic acids, lipids and small molecules can either be repaired or eliminated from the body. His lab has analyzed protein-repair systems and novel types of enzymes that may contribute to reducing this buildup of damage in aging organisms.

Specifically, Clarke's team discovered and characterized the repair system involving the enzyme L-isoaspartyl methyltransferase, or PCMT. Early research on this enzyme's ability to repair defective proteins demonstrated that mice lacking sufficient PCMT had a significant increase in the number of damaged proteins in their tissues, particularly in the brain. Deficiencies in this enzyme have been linked to epilepsy and may also play a role in several degenerative diseases.

According to Clarke, understanding such pathways may help spur the future development of interventions to enhance these repair systems in the elderly, helping address declines in muscle strength, lung capacity, mental status, eye-lens clarity, heart output and other losses of function.

Clarke added that we may now be at the tip of the iceberg in our understanding of how many repair activities exist and how these activities may be manipulated for healthy living, particularly with diet and pharmaceuticals.

"I'm excited to accept the appointment to the Plott Chair and to continue our research in this critical field," said Clarke, who also directs UCLA's Cellular and Molecular Biology Training Program.

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UCLA Chemist Steven G. Clarke Named to Endowed Chair in Gerontology

‘Promiscuous’ enzymes still common in metabolism

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SAN DIEGO Open an undergraduate biochemistry textbook and you will learn that enzymes are highly efficient and specific in catalyzing chemical reactions in living organisms, and that they evolved to this state from their sloppy and promiscuous ancestors to allow cells to grow more efficiently. This fundamental paradigm is being challenged in a new study by bioengineers at the University of California, San Diego, who reported in the journal Science what a few enzymologists have suspected for years: Many enzymes are still pretty sloppy and promiscuous, catalyzing multiple chemical reactions in living cells, for reasons that were previously not well understood.

In this study, the research team, led by Bernhard Palsson, Galetti Professor of Bioengineering at the UC San Diego Jacobs School of Engineering, brought together decades of work on the behavior of individual enzymes to produce a genome-scale model of E. coli metabolism and report that at least 37 percent of its enzymes catalyze multiple metabolic reactions that occur in an actively growing cell.

Weve been able to stitch all of the enzymes together into one giant model, giving us a holistic view of what has been driving the evolution of enzymes and found that it isnt quite what weve thought it to be, said Palsson.

When organisms evolve, it is the genes or proteins that change. Therefore, gene and protein evolution has classically been studied one gene at a time. However in this work, Palsson and his colleagues, introduce an important paradigm shift by demonstrating that the evolution of individual proteins and enzymes is influenced by the function of all of the other enzymes in an organism, and how they all work together to support the growth rate of the cell.

Using a whole-cell model of metabolism, the research team found that the more essential an enzyme is to the growth of the cell, the more efficient it needs to be; meanwhile, enzymes that only weakly contribute to cell growth can remain sloppy. The study found three major reasons why some enzymes have evolved to be so efficient, while others have not:

Our study found that the functions of promiscuous enzymes are still used in growing cells, but the sloppiness of these enzymes is not detrimental to growth. They are much less sensitive to changes in the environment and not as necessary for efficient cell growth, said Nathan Lewis, who earned a Ph.D. in bioengineering at the Jacobs School in March and is now a postdoctoral fellow at Harvard Medical School.

This study is also a triumph in the emerging field of systems biology, which leverages the power of high-performance computing and an enormous amount of available data from the life sciences to simulate activities such as the rates of reactions that break down nutrients to make energy and new cell parts. This study sheds light on the vast number of promiscuous enzymes in living organisms and shifts the paradigm of research in biochemistry to a holistic level, said Lewis. The insights found in our work also clearly show that fine-grained knowledge can be obtained about individual proteins while using large-scale models. This concept will yield immediate and more distant results.

Our teams findings could also inform other research efforts into which enzymes require further study for overlooked promiscuous activities, said Hojung Nam, a postdoctoral researcher in Palssons lab. Besides testing and characterizing more enzymes for potential promiscuous activities, enzyme promiscuity could have far-reaching impacts as scientists try to understand how unexpected promiscuous activities of enzymes contribute to diseases such as leukemia and brain tumors, said Nam.

Funding was provided by the U.S. Department of Energy and National Institutes of Health (DE-SC0004917, DE-FG02-09ER25917, and 2R01GM057089-13) and a fellowship from the National Science Foundation (NSF GK-12 742551).

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‘Promiscuous’ enzymes still common in metabolism

Local Weather

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Sangeeta Tohani, 19, of Longwood Gardens, Barkingside performed a special dance routine in front of 80,000 people in the Olympic Stadium alongside fellow dancers from Sakthi Fine Arts, The Crescent, Gants Hill.

The Queen Mary University student auditioned back in February and she was soon told she had been selected after learning Indian classical dancing since she was about five years old.

She said: From the very beginning the whole experience has been incredible. We saw people auditioning with disabilities, who were all catered for, which was really inspiring.

I was determined to get involved in the Paralymics after missing out on the Olympics, which I watched constantly. And knowing that Id be performing just around the corner from where I live was amazing.

Miss Tohani, who also performed during the Torch Relay in Redbridge, was part of the Navigation segment of the ceremony representing the sea.

She said: Despite the steps being fairly simple I forgot them in the dress rehearsal because everything was so overwhelming and to see everything come together in the stadium left me gobsmacked.

Miss Tohani, who described the experience as surreal had been practising with the large group of dancers for ten hours a day for the past three weeks in preparation for the performance.

She added: It started to rain during our section, which was quite late on, leaving the floor really wet; but we didnt even think about it.

Once our part was almost over everyone got really emotional because we didnt want it to end. I have met so many people who I wouldnt normally get a chance to meet.

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Major advances in understanding the regulation and organization of the human genome

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Public release date: 5-Sep-2012 [ | E-mail | Share ]

Contact: Angela Hopp ahopp@asbmb.org 240-283-6614 American Society for Biochemistry and Molecular Biology

The National Human Genome Research Institute today announced the results of a five-year international study of the regulation and organization of the human genome. The project is named ENCODE, which stands for the Encyclopedia of DNA Elements. In conjunction with the release of those results, the Journal of Biological Chemistry has published a series of reviews that focus on several aspects of the findings.

"The ENCODE project not only generated an enormous body of data about our genome, but it also analyzed many issues to better understand how the genome functions in different types of cells. These insights from integrative analyses are really stories about how molecular machines interact with each other and work on DNA to produce the proteins and RNAs needed for each cell to function within our bodies," explains Ross Hardison of Pennsylvania State University, one of the JBC authors.

Hardison continued: "The Journal of Biological Chemistry recognized that the results from the ENCODE project also would catalyze much new research from biochemists and molecular biologists around the world. Hence, the journal commissioned these articles not only to communicate the insights from the papers now being published but also to stimulate more research in the broader community."

The human genome consists of about 3 billion DNA base pairs, but only a small percentage of DNA actually codes for proteins. The roles and functions of the remaining genetic information were unclear to scientists and even referred to as "junk DNA." But the results of the ENCODE project is filling this knowledge gap. The findings revealed that more than 80 percent of the human genome is associated with biological function.

The study showed in a comprehensive way that proteins switch genes on and off regularly and can do so at distances far from the genes they regulate and it determined sites on chromosomes that interact, the locations where chemical modifications to DNA can influence gene expression, and how the functional forms of RNA can regulate the expression of genetic information.

The results establish the ways in which genetic information is controlled and expressed in specific cell types and distinguish particular regulatory regions that may contribute to diseases.

"The deeper knowledge of gene regulation coming from the ENCODE project will have a positive impact on medical science," Hardison emphasizes. For example, recent genetic studies have revealed many genomic locations that can affect a person's susceptibility to common diseases. The ENCODE data show that many of these regions are involved in gene regulation, and the data provide hypotheses for how variations in these regions can affect disease susceptibility, adds Hardison.

The effort behind the ENCODE project was extraordinary. More than 440 scientists in 32 labs in United States, the United Kingdom, Spain, Singapore and Japan performed more than 1,600 sets of experiments on 147 types of tissue. The results were published today in one main integrative paper and five other papers in the journal Nature, 18 papers in Genome Research and six papers in Genome Biology.

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Major advances in understanding the regulation and organization of the human genome

'Promiscuous' enzymes still prevalent in metabolism

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Enzymes are often thought to be specific, catalyzing only one reaction in a cell (left). However, some more promiscuous enzymes have many functions and catalyze many reactions in a cell. This study shows that promiscuous enzymes play a larger part in cell growth than previously thought. Credit: Courtesy of Systems Biology Research Group, UC San Diego, Jacobs School of Engineering

Open an undergraduate biochemistry textbook and you will learn that enzymes are highly efficient and specific in catalyzing chemical reactions in living organisms, and that they evolved to this state from their "sloppy" and "promiscuous" ancestors to allow cells to grow more efficiently. This fundamental paradigm is being challenged in a new study by bioengineers at the University of California, San Diego, who reported in the journal Science what a few enzymologists have suspected for years: many enzymes are still pretty sloppy and promiscuous, catalyzing multiple chemical reactions in living cells, for reasons that were previously not well understood.

In this study, the research team, led by Bernhard Palsson, Galetti Professor of Bioengineering at the UC San Diego Jacobs School of Engineering, brought together decades of work on the behavior of individual enzymes to produce a genome-scale model of E. coli metabolism and report that at least 37 percent of its enzymes catalyze multiple metabolic reactions that occur in an actively growing cell.

"We've been able to stitch all of the enzymes together into one giant model, giving us a holistic view of what has been driving the evolution of enzymes and found that it isn't quite what we've thought it to be," said Palsson.

When organisms evolve, it is the genes or proteins that change. Therefore, gene and protein evolution has classically been studied one gene at a time. However in this work, Palsson and his colleagues, introduce an important paradigm shift by demonstrating that the evolution of individual proteins and enzymes is influenced by the function of all of the other enzymes in an organism, and how they all work together to support the growth rate of the cell.

Enlarge

Each gene and protein in a cell has a function, and many of these functions are linked to each other. Thus, as organisms evolve, the collective functions of all genes and proteins in the cells influence the evolution of each gene or protein. Credit: Courtesy of Systems Biology Research Group, UC San Diego, Jacobs School of Engineering

"Our study found that the functions of promiscuous enzymes are still used in growing cells, but the sloppiness of these enzymes is not detrimental to growth. They are much less sensitive to changes in the environment and not as necessary for efficient cell growth," said Nathan Lewis, who earned a Ph.D. in bioengineering at the Jacobs School in March and is now a postdoctoral fellow at Harvard Medical School.

This study is also a triumph in the emerging field of systems biology, which leverages the power of high-performance computing and an enormous amount of available data from the life sciences to simulate activities such as the rates of reactions that break down nutrients to make energy and new cell parts. "This study sheds light on the vast number of promiscuous enzymes in living organisms and shifts the paradigm of research in biochemistry to a holistic level," said Lewis. "The insights found in our work also clearly show that fine-grained knowledge can be obtained about individual proteins while using large-scale models." This concept will yield immediate and more distant results.

"Our team's findings could also inform other research efforts into which enzymes require further study for overlooked promiscuous activities," said Hojung Nam, a postdoctoral researcher in Palsson's lab. "Besides testing and characterizing more enzymes for potential promiscuous activities, enzyme promiscuity could have far-reaching impacts as scientists try to understand how unexpected promiscuous activities of enzymes contribute to diseases such as leukemia and brain tumors," said Nam.

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'Promiscuous' enzymes still prevalent in metabolism

NDSU Research Connects the Dots to Renewable Energy Future

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Newswise Svetlana Kilina, Ph.D., assistant professor of chemistry and biochemistry at North Dakota State University, Fargo, has received a $750,000 five-year award from the U.S. Department of Energy Office of Science Early Career Research Program. Funding will be used to conduct research outlined in Dr. Kilinas proposal titled Modeling of Photoexcited Process at Interfaces of Functionalized Quantum Dots.

Dr. Kilinas research occurs at the intersection of renewable energy, high-performance computing, nanotechnology and chemistry. Only 68 awardees were selected from a pool of about 850 university- and national laboratory-based applicants, based on peer review by outside scientific experts.

Quantum dots are nanocrystals discovered by scientists in the 1980s. Ranging in size from two to 10 nanometers, billions of them could fit on the head of a pin. Their tiny sizes belie the Herculean impact they could make in semiconductors and energy. Dr. Kilinas work centers on new generation solar cells and fuel cells using quantum-dot-based materials.

Materials at the nanoscale level behave differently than at larger scales. Energized quantum dots absorb and emit light. The color of the light depends on the size of the dot. In addition, one quant of light can generate more than two carriers of electric current (two electrons-hole pairs instead of one) in quantum dots. As a result, quantum dots could convert energy to light or vice versa more efficiently than conventional energy materials based on bulk semiconductors such as silicon. That makes quantum dots very promising materials for solar cells and other energy applications.

One of the main obstacles in the synthesis of quantum dots is the controllable chemistry of the quantum dot surface, said Dr. Kilina. Due to their nanosize, the dots are extremely chemically reactive, and different organic molecules from solvent/air environment interact with the surface of the quantum dot during and after synthesis. These molecules cover the surface of the quantum dot like a shell, influencing its optical and electronic properties.

Dr. Kilina uses supercomputers to conduct computer-simulated experiments, investigate and advance her research in this field. Her goal is to generate theoretical insights to the surface chemistry of quantum dots, which are critical to design efficient quantum-dot-based materials for solar energy conversion and lighting applications.

To apply her model and algorithmic methods, Dr. Kilinas research group uses supercomputers at the NDSU Center for Computationally Assisted Science and Technology, in addition to Department of Energy and Los Alamos National Laboratory leadership-class, high-performance computing facilities. The combination of NDSU supercomputing and government facilities substantially reduces the amount of time needed for the massive calculations used in this research.

Dr. Kilinas research aims to gain fundamental understanding of nanomaterials at the molecular and electronic level, said Dr. Greg Cook, chair of NDSUs Department of Chemistry and Biochemistry. Insights gained from this research will enable the progression of solar energy technology to help solve the worlds energy challenges. The Department of Energy award recognizes Dr. Kilinas unique expertise in the area of theoretical modeling of these materials critical for the future, said Cook.

Dr. Kilinas research addresses fundamental questions of modern materials science that affect the design and manufacture of new-generation energy conversion devices. To design and manufacture such devices requires developing new multi-functional materials with controllable properties. As part of Dr. Kilinas work centered around new generation solar cells and fuel cells, she develops and applies a new generation non-adiabatic photoinduced dynamics methodology that simultaneously includes electron-hole coupling response for excitonic effects and exciton-phonon coupling critical in photoexcitation and couplings between electronics and crystal-lattice vibrations responsible for energy-to-heat losses.

It is anticipated that the acquired theoretical knowledge gained from the research at NDSU will help better explain and interpret experimental data and could facilitate rational design of new nanostructures with desired optical, transport, and light harvesting properties that are fundamental to a myriad of clean energy technologies.

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NDSU Research Connects the Dots to Renewable Energy Future

Senior Focus: New imaging device helps detect brain changes

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Brain imaging helps to understand how the brain works, aids in the diagnosis of neurological diseases and guides treatments. Positron emission tomography or PET is an imaging technique that uses trace amounts of radioactive drugs to visualize the function and biochemistry of the brain.

Imaging researchers now have developed new PET tracers to detect changes in the brain caused by Alzheimer's dementia and other neurodegenerative disease. These diseases damage and ultimately kill large numbers of brain cells (neurons) and thus lead to severe disability and death.

Neurodegenerative diseases cause specific patterns of injury and biochemical abnormalities in the brain. Until recently, these changes could only be measured after death by examining brain tissue using a microscope. One of the exciting developments in PET imaging is the availability of new agents that can detect beta-amyloid plaques, one of the key abnormalities in Alzheimer's disease, in the living human brain. Plaques may develop in the brain over a decade before Alzheimer's symptoms develop.

Neurologists and other dementia specialists currently rely primarily on information gathered from the patient and family, physical examination and cognitive tests to diagnose Alzheimer's dementia. In some cases, determining the cause of a patient's cognitive problems can be challenging, and now PET imaging can help doctors and patients be more confident in the diagnosis.

Two clinically used PET imaging tests for patients are being evaluated for dementia. A PET tracer called FDG measures the brain's use of glucose, a simple sugar that serves as the brain's major source of energy. In dementia due to Alzheimer's disease, decreased glucose metabolism in specific brain regions supports a diagnosis of Alzheimer's disease.

The other PET imaging test for patients with cognitive impairment uses a different PET tracer, florbetapir, which binds to beta-amyloid plaques that occur in Alzheimer's disease. This PET tracer was approved for clinical use by the Food and Drug Administration in April 2012. Amyloid PET imaging can show the presence or absence of abnormally increased plaques in the brain. Low plaque levels (a negative amyloid PET study) reduce the likelihood that a patient's cognitive problems are due to Alzheimer's disease. Higher plaque levels are present in Alzheimer's disease, but a positive amyloid PET scan can occur with other neurologic diseases and in older people without cognitive problems.

Both FDG and amyloid PET are only part of the evaluation of patients with dementia or other cognitive disorders. Neither of these tests alone can make specific diagnoses. PET imaging in patients with cognitive impairment should be ordered by physicians experienced in the diagnosis and treatment of patients of these conditions when the results will help in clinical decision making.

Dr. Jonathan McConathy is an assistant professor of radiology at Washington University who is board certified in diagnostic radiology and nuclear medicine. For information about brain PET studies at Washington University, call 314-362-4738.

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Senior Focus: New imaging device helps detect brain changes

'Promiscuous' enzymes still prevalent in metabolism: Challenges fundamental notion of enzyme specificity and efficiency

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ScienceDaily (Aug. 30, 2012) Open an undergraduate biochemistry textbook and you will learn that enzymes are highly efficient and specific in catalyzing chemical reactions in living organisms, and that they evolved to this state from their "sloppy" and "promiscuous" ancestors to allow cells to grow more efficiently. This fundamental paradigm is being challenged in a new study by bioengineers at the University of California, San Diego, who reported in the journal Science what a few enzymologists have suspected for years: many enzymes are still pretty sloppy and promiscuous, catalyzing multiple chemical reactions in living cells, for reasons that were previously not well understood.

In this study, the research team, led by Bernhard Palsson, Galetti Professor of Bioengineering at the UC San Diego Jacobs School of Engineering, brought together decades of work on the behavior of individual enzymes to produce a genome-scale model of E. coli metabolism and report that at least 37 percent of its enzymes catalyze multiple metabolic reactions that occur in an actively growing cell.

"We've been able to stitch all of the enzymes together into one giant model, giving us a holistic view of what has been driving the evolution of enzymes and found that it isn't quite what we've thought it to be," said Palsson.

When organisms evolve, it is the genes or proteins that change. Therefore, gene and protein evolution has classically been studied one gene at a time. However in this work, Palsson and his colleagues, introduce an important paradigm shift by demonstrating that the evolution of individual proteins and enzymes is influenced by the function of all of the other enzymes in an organism, and how they all work together to support the growth rate of the cell.

Using a whole-cell model of metabolism, the research team found that the more essential an enzyme is to the growth of the cell, the more efficient it needs to be; meanwhile, enzymes that only weakly contribute to cell growth can remain 'sloppy.' The study found three major reasons why some enzymes have evolved to be so efficient, while others have not:

Enzymes that are used more extensively by the organism need to be more efficient to avoid waste. To increase efficiency, they evolve to catalyze one specific metabolic reaction. When enzymes are responsible for catalyzing reactions that are necessary for cell growth and survival, they are specific in order to avoid interference from molecules that are not needed for cell growth and survival.

Since organisms have to adapt to dynamic and noisy environments, they sometimes need to have careful control of certain enzyme activities in order to avoid wasting energy and prepare for anticipated nutrient changes. Evolving higher specificity makes these enzymes easier to control.

"Our study found that the functions of promiscuous enzymes are still used in growing cells, but the sloppiness of these enzymes is not detrimental to growth. They are much less sensitive to changes in the environment and not as necessary for efficient cell growth," said Nathan Lewis, who earned a Ph.D. in bioengineering at the Jacobs School in March and is now a postdoctoral fellow at Harvard Medical School.

This study is also a triumph in the emerging field of systems biology, which leverages the power of high-performance computing and an enormous amount of available data from the life sciences to simulate activities such as the rates of reactions that break down nutrients to make energy and new cell parts. "This study sheds light on the vast number of promiscuous enzymes in living organisms and shifts the paradigm of research in biochemistry to a holistic level," said Lewis. "The insights found in our work also clearly show that fine-grained knowledge can be obtained about individual proteins while using large-scale models." This concept will yield immediate and more distant results.

"Our team's findings could also inform other research efforts into which enzymes require further study for overlooked promiscuous activities," said Hojung Nam, a postdoctoral researcher in Palsson's lab. "Besides testing and characterizing more enzymes for potential promiscuous activities, enzyme promiscuity could have far-reaching impacts as scientists try to understand how unexpected promiscuous activities of enzymes contribute to diseases such as leukemia and brain tumors," said Nam.

Originally posted here:
'Promiscuous' enzymes still prevalent in metabolism: Challenges fundamental notion of enzyme specificity and efficiency

Science Study Shows 'Promiscuous' Enzymes Still Prevalent in Metabolism

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Newswise Open an undergraduate biochemistry textbook and you will learn that enzymes are highly efficient and specific in catalyzing chemical reactions in living organisms, and that they evolved to this state from their sloppy and promiscuous ancestors to allow cells to grow more efficiently. This fundamental paradigm is being challenged in a new study by bioengineers at the University of California, San Diego, who reported in the journal Science what a few enzymologists have suspected for years: many enzymes are still pretty sloppy and promiscuous, catalyzing multiple chemical reactions in living cells, for reasons that were previously not well understood.

In this study, the research team, led by Bernhard Palsson, Galetti Professor of Bioengineering at the UC San Diego Jacobs School of Engineering, brought together decades of work on the behavior of individual enzymes to produce a genome-scale model of E. coli metabolism and report that at least 37 percent of its enzymes catalyze multiple metabolic reactions that occur in an actively growing cell.

Weve been able to stitch all of the enzymes together into one giant model, giving us a holistic view of what has been driving the evolution of enzymes and found that it isnt quite what weve thought it to be, said Palsson.

When organisms evolve, it is the genes or proteins that change. Therefore, gene and protein evolution has classically been studied one gene at a time. However in this work, Palsson and his colleagues, introduce an important paradigm shift by demonstrating that the evolution of individual proteins and enzymes is influenced by the function of all of the other enzymes in an organism, and how they all work together to support the growth rate of the cell.

Using a whole-cell model of metabolism, the research team found that the more essential an enzyme is to the growth of the cell, the more efficient it needs to be; meanwhile, enzymes that only weakly contribute to cell growth can remain sloppy. The study found three major reasons why some enzymes have evolved to be so efficient, while others have not:

Enzymes that are used more extensively by the organism need to be more efficient to avoid waste. To increase efficiency, they evolve to catalyze one specific metabolic reaction. When enzymes are responsible for catalyzing reactions that are necessary for cell growth and survival, they are specific in order to avoid interference from molecules that are not needed for cell growth and survival.

Since organisms have to adapt to dynamic and noisy environments, they sometimes need to have careful control of certain enzyme activities in order to avoid wasting energy and prepare for anticipated nutrient changes. Evolving higher specificity makes these enzymes easier to control.

Our study found that the functions of promiscuous enzymes are still used in growing cells, but the sloppiness of these enzymes is not detrimental to growth. They are much less sensitive to changes in the environment and not as necessary for efficient cell growth, said Nathan Lewis, who earned a Ph.D. in bioengineering at the Jacobs School in March and is now a postdoctoral fellow at Harvard Medical School.

This study is also a triumph in the emerging field of systems biology, which leverages the power of high-performance computing and an enormous amount of available data from the life sciences to simulate activities such as the rates of reactions that break down nutrients to make energy and new cell parts. This study sheds light on the vast number of promiscuous enzymes in living organisms and shifts the paradigm of research in biochemistry to a holistic level, said Lewis. The insights found in our work also clearly show that fine-grained knowledge can be obtained about individual proteins while using large-scale models. This concept will yield immediate and more distant results.

Our teams findings could also inform other research efforts into which enzymes require further study for overlooked promiscuous activities, said Hojung Nam, a postdoctoral researcher in Palssons lab. Besides testing and characterizing more enzymes for potential promiscuous activities, enzyme promiscuity could have far-reaching impacts as scientists try to understand how unexpected promiscuous activities of enzymes contribute to diseases such as leukemia and brain tumors, said Nam.

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Science Study Shows 'Promiscuous' Enzymes Still Prevalent in Metabolism

Project MICREAgents: self-assembling smart microscopic reagents to pioneer pourable electronics

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29.08.2012 - (idw) Ruhr-Universitt Bochum

First place in an EU competitive call on Unconventional Computing was awarded to a collaborative proposal coordinated by Prof. John McCaskill from the RUB Faculty of Chemistry and Biochemistry. The project MICREAgents plans to build autonomous self-assembling electronic microreagents that are almost as small as cells. They will exchange chemical and electronic information to jointly direct complex chemical reactions and analyses in the solutions they are poured into. The EU supports the project within the FP7 programme with 3.4 million Euros for three years. Turning chemistry inside-out Self-assembling smart microscopic reagents to pioneer pourable electronics 3.4 million Euros from EU programme for international research project

First place in an EU competitive call on Unconventional Computing was awarded to a collaborative proposal coordinated by Prof. John McCaskill from the RUB Faculty of Chemistry and Biochemistry. The project MICREAgents plans to build autonomous self-assembling electronic microreagents that are almost as small as cells. They will exchange chemical and electronic information to jointly direct complex chemical reactions and analyses in the solutions they are poured into. This is a form of embedded computation to compute is to construct in which for example the output is a particular catalyst or coating needed in the (input) local chemical environment. The EU supports the project within the FP7 programme with 3.4 million Euros for three years. Four research groups at RUB will join forces with top teams across Europe, from Israel and New Zealand.

Self-assembling electronic agents

In order to create this programmable microscale electronic chemistry, MICREAgents (Microscopic Chemically Reactive Electronic Agents) will contain electronic circuits on 3D microchips, called lablets. The lablets have a diameter of less than 100 m and self-assemble in pairs or like dominos to enclose transient reaction compartments. They can selectively concentrate, process, and release chemicals into the surrounding solution, under local electronic control, in a similar way to which the genetic information in cells controls local chemical processes. The reversible pairwise association allows the lablets to transfer information from one to another.

Translating electronic signals into chemical processes

The lablet devices will integrate transistors, supercapacitors, energy transducers, sensors and actuators, and will translate electronic signals into constructive chemical processing as well as record the results of this processing. Instead of making chemical reactors to contain chemicals, the smart MICREAgents will be poured into chemical mixtures, to organize the chemistry from within. Ultimately, such microreactors, like cells in the bloodstream, will open up the possibility of controlling complex chemistry from the inside out.

The self-assembling smart micro reactors can be programmed for molecular amplification and other chemical processing pathways that start from complex mixtures, concentrate and purify chemicals, perform reactions in programmed cascades, sense reaction completion, and transport and release products to defined locations. MICREAgents represent a novel form of computation intertwined with construction. By embracing self-assembly and evolution, they are a step towards a robust and evolvable realization of John von Neumanns universal construction machine vision. Although these nanoscale structures will soon be sufficiently complex to allow self-replication of their chemical and electronic information, they will not present a proliferative threat to the environment, because they depend for their function on the electronic circuit layer that is fabricated as part of their substrate.

RUB collaborators

For the project, Prof. Dr. John S. McCaskill (Microsystems Chemistry and Biological Information Technology) collaborates with Prof. Dr. Gnter von Kiedrowski (Bioorganic Chemistry), Prof. Dr. Jrgen Oehm (Analog Integrated Circuits) and Dr. Pierre Mayr (Integrated Digital Circuits). McCaskills and von Kiedrowskis labs at RUB have already joined forces in previous European Projects forging a path towards artificial cells. The ECCell project, for example, that finished in February this year, has laid the foundation for an electronic chemical cell. There, the electronics and microfluidics were exterior to the chemistry: in MICREAgents this is being turned inside out.

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Project MICREAgents: self-assembling smart microscopic reagents to pioneer pourable electronics

Scaled-Down: New Nano Device Can Weigh Single Molecules

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A tiny resonating beam, just 10 millionths of a meter in length, can measure the mass of a molecule or nanoparticle in real time

By John Matson

WEIGHTY MATTERS: The diagonal beam in this image can detect the presence of single molecules and determine their mass. Image: Caltech/Scott Kelber and Michael Roukes

Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...

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Dieters and exercise buffs might feel better about their progress if they tracked their weight loss in daltons. Even a short jog can help you shed a few septillion daltons, a unit of mass often used in biochemistry that is equivalent to the atomic mass unit. (Of course, no weight-conscious individual would want to know their full weight in this unitthe average American male weighs approximately 5 X 1028 daltons.)

Even the megadalton, or one million daltons, is a tiny unit of measurea gold particle five nanometers across weighs in at just a few megadaltons. (One nanometer is a billionth of a meter.) But researchers at the California Institute of Technology and CEALeti, a government-funded research organization in Grenoble, France, have built a scale that weighs single objects even lighter than a megadalton, including nanoparticles and human antibody molecules. The device is the first of its kind to determine the masses of individual molecules and nanoparticles in real time, the researchers reported in a study published online August 26 in Nature Nanotechnology. (Scientific American is part of Nature Publishing Group.)

The heart of the device is a nanoelectromechanical resonatora tiny beam of silicon vibrating at two tones simultaneously. "It's like vibrating a guitar string at the fundamental and a harmonic," says study co-author Michael Roukes, a Caltech physicist. "We're continuously strumming it with an electrostatic excitation." The beam runs diagonally across the photo (above); it measures 10 microns long and 300 nanometers wide. (A micron is one millionth of a meter.)

Tiny arms connecting the ends of the beam to the rest of the device convert the resonator's vibrations into an electrical signal via a phenomenon known as the piezoresistive effect. "The smallest pieces there are flexed slightly, and when they're flexed their resistance changes," Roukes says. "And so we can read out the motion as a change in resistance." A single molecule landing on the beam shifts the frequency of the two tones downward, and from the accompanying change in resistance the researchers can deduce both the mass of the particle and where it landed along the beam.

The device's sensitivity to single molecules allowed the researchers to perform mass spectroscopyidentifying the various particles in a mixture by their masseson collections of gold nanoparticles five and 10 nanometers in diameter, as well as on the antibody molecule immunoglobulin M, which weighs just under one megadalton. (The natural molecules proved much more consistent in their construction than did the man-made nanoparticles, whose masses fluctuated by a factor of five or so from particle to particle.)

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Scaled-Down: New Nano Device Can Weigh Single Molecules

Histone-modifying proteins, not histones, remain associated with DNA through replication

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Public release date: 23-Aug-2012 [ | E-mail | Share ]

Contact: Steve Graff stephen.graff@jefferson.edu 215-955-5291 Thomas Jefferson University

PHILADELPHIAIt's widely accepted that molecular mechanisms mediating epigenetics include DNA methylation and histone modifications, but a team from Thomas Jefferson University has evidence to the contrary regarding the role of histone modifications.

A study of Drosophila embryos from Jefferson's Department of Biochemistry and Molecular Biology published ahead of print in Cell August 23 found that parental methylated histones are not transferred to daughter DNA. Rather, after DNA replication, new nucleosomes are assembled from newly synthesized unmodified histones.

"Essentially, all histones are going away during DNA replication and new histones, which are not modified, are coming in," said Alexander M. Mazo, Ph.D., professor of Biochemistry and Molecular Biology at Jefferson, and a member of Jefferson's Kimmel Cancer Center. "In other words, what we found is that histone modifying proteins are hiding on the way over replicating DNA, instead of histones 'jumping' over as currently thought."

"What this paper tells us," he continues, "is that these histone modifying proteins somehow are able to withstand the passage of the DNA replication machinery. They remained seated on their responsive binding sites, and in all likelihood they will re-establish histone modification and finalize the chromatin structure that allows either activation or repression of the target gene."

The team suggests that since it appears these histone modifying proteinsthe Trithorax-group (TrxG), which maintain gene expression, and the Polycomb-group (PcG), which plays a role in epigenetic silencing of genesre-establish the histone code on newly assembled unmethylated histones, they may act as epigenetic marks.

Epigenetics is the study of heritable changes in gene expression caused by mechanisms other than changes in the underlying DNA sequence. Epigenetic marks have become an important focus in recent years because they are thought to have the potential to explain mechanisms of aging, human development, and the origins of diseases, like cancer, heart disease, and mental illness.

According to widely-accepted models applied today, the tails of methylated histones turn genes in DNA "on" or "off" by loosening or tightening nucleosome structure, thus changing the accessibility of transcription factors and other proteins to DNA.

"People believe that everything gets worked off of DNA during the replication process and that these methylated histones act as epigenetic marks, since they are believed to rapidly jump from parental to daughter DNA" said Dr. Mazo. "But there is no experimental evidence to back this up."

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Histone-modifying proteins, not histones, remain associated with DNA through replication

Tribune Readers’ Views for Thursday, Aug. 23

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Oak Hill High staff is commended

I would like to commend the staff at Oak Hill High School for the excellent education you provided our children. Our son returned to Marshall University as a senior and graduate with a biochemistry degree, then will move on to graduate or medical school. Our daughter moved in on Aug. 22 with 25 credit hours achieved through the hard work and dedication of those professionals at Oak Hill High School. She will begin her journey towards receiving her biochemistry degree and becoming a pediatric oncologist.

I am writing this article not only to commend educators who strive to make a difference, but also to help young people realize that dreams are not impossible. Sometimes they are hard to achieve because of the dedication and hard work that is needed to accomplish the goal, but if its worth the effort to make Gods world a better place, then do it.

My question to all of the wonderful students I have been blessed by is simply this: Why did God create you and what is your purpose in life? If you cant answer this question, then our world has no future.

Cathy Broughman

Oak Hill

Avoid buying puppies from roadside peddlers

If you have been to the Fayette Town Center more than a few times, you have surely seen people in the median selling pure-bred or designer breed puppies from their vehicles with a handmade sign. I would like to encourage readers not to walk, but run away from these people.

The plaza tried to solve the problem with signage, but the signs soon disappeared and the puppy peddlers returned. A puppy mill or a backyard breeder is an extremely common business that often operates underground, and right here in Fayette County.

The operator chooses a breed of the current fad (often a toy breed) and forces dogs of that breed or breeds to reproduce at an unhealthy frequency in deplorable conditions. The mothers do not receive adequate care, socialization, recreation or affection in order to keep operating costs at a minimum. Some spend most of their lives in a cage the size of your dishwasher.

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Tribune Readers’ Views for Thursday, Aug. 23

NDSU Faculty Receives NSF Funding for Chemistry Research

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Newswise Sivaguru (Siva) Jayaraman, Ph.D., associate professor of chemistry and biochemistry at North Dakota State University, Fargo, has received a three-year, $429,500 award from the National Science Foundation (NSF) to conduct research outlined in his proposal titled Light Induced Enantiospecific Chiral Transfer in Solution. The funding also provides research opportunities to graduate and undergraduate students to develop environmentally benign, green strategies to perform chemical reactions.

The research program in Dr. Sivas group focuses on using light to transfer molecular chirality in photochemical reactions (reactions initiated by light) to produce molecules that are chiral (have two non-superimposable mirror images) and make only one of the two possible forms (a single enantiomer).

Based on the funding from the National Science Foundation, his research group will study light-induced enantiospecific chiral transfer in solution. One of the research goals is to gain a fundamental understanding of interaction of light with photoreactive substrates, coupled with an intricate control over molecular reactivity, dynamics and non-bonding interactions to enhance stereoselectivity in the photoproducts.

Synthesizing chiral compounds with high stereoselectivity during light-induced transformations provides an opportunity to develop sustainable strategies with minimal impact on the environment, said Dr. Jayaraman.

Students learn how modern chemical methods can be used for synthesizing compounds with minimal environmental impact. With this most recent NSF funding, students involved in the proposed investigations will learn both traditional techniques to characterize and evaluate asymmetric induction during enantiospecific phototransformations and modern spectroscopic methods and characterization techniques to assess excited state reactivity.

The award is a renewal grant of Dr. Jayaramans CAREER award, which includes research opportunities for NDSU students. His research also provides opportunities to area high school students through a program called PICNICS (Parents Involvement with Children, Nurturing Intellectual Curiosity in Science).

As part of the PICNICS program, top area high school students conduct a variety of research each summer alongside graduate students and postdoctoral fellows at the Department of Chemistry and Biochemistry, NDSU, Fargo. The PICNICS program was developed by Dr. Jayaraman as an outreach component in his NSF CAREER award to engage high school students and their parents about recent science and technology advancements and to encourage high school juniors and seniors to consider science as a career path.

Dr. Sivaguru (Siva) Jayaraman joined the faculty at NDSU in 2006. He was promoted to associate professor in 2011. He previously received an NSF CAREER award in 2008, a Grammaticakis-Neumann Prize from the Swiss Chemical Society in 2010, a Young-investigator award from the Inter-American Photochemical Society (I-APS) in 2011, and a Young-investigator award from Sigma Xi in 2012.

At NDSU, Dr. Jayaraman received the 2010 Excellence in Research Award, 2011 Excellence in Teaching award and 2012 Peltier Award for Innovation in Teaching. He completed a post-doctoral fellowship at Columbia University, New York, N.Y., after receiving his Ph.D. from Tulane University, New Orleans, La. He received a masters degree in chemistry from the Indian Institute of Technology, Madras, India, and completed a bachelors degree in chemistry from St. Josephs College, Bharathidasan University, Trichy, India.

For more info regarding Dr. Sivaguru Jayaramans research, teaching and outreach visit http://sivagroup.chem.ndsu.nodak.edu/

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NDSU Faculty Receives NSF Funding for Chemistry Research

Purdue grad hopes to grow Tymora startup into 'multimillion-dollar company'

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Anton Iliuk never expected to be an entrepreneur.

Now, the former Purdue University biochemistry students doctoral project to develop new technology that can help pinpoint potential targets for cancer therapy has transformed into a growing startup in Purdue Research Park.

Iliuks former adviser, biochemistry associate professor W. Andy Tao, is his business partner.

Most science majors have two paths, Iliuk said. One is academia. One is industry. This is the path less traveled. Im not a business guy.

But the companys first product, PolyMAC, still managed to generate sales of nearly $50,000 in five months for his company, Tymora Analytical Operations LLC.

Id like to turn this into a multimillion-dollar company, Iliuk said. If you dont believe, nobody else will.

Iliuk, the companys president and chief technology officer, said a realistic goal for next year would be to double the sales of PolyMAC, which analyzes tissue modification on a cellular level.

You send in a fishing net, you try to pick up everything there is, sort through it and see what has changed from normal tissue to cancer tissue, Iliuk said.

The next step for Tymora is to get its next product, pIMAGO, to market. Iliuk said the goal of pIMAGO is to cut the cost associated with the early stages of drug development by showing which drugs will be more effective.

Its sort of a launch pad, Iliuk said. Were trying to improve the way people do lab research.

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Purdue grad hopes to grow Tymora startup into 'multimillion-dollar company'

The American Society for Microbiology honors Andrew Lovering

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Public release date: 22-Aug-2012 [ | E-mail | Share ]

Contact: Garth Hogan ghogan@asmusa.org American Society for Microbiology

Andrew Lee Lovering, Ph.D., School of Biosciences, University of Birmingham, has received a 2012 ICAAC Young Investigator Award for his seminal work on the structural biology and biochemistry of the proteins that synthesize and modify cell walls in bacteria. Natalie Strynadka, University of British Columbia, describes the significance of Lovering's work: "his spectacular abilities in structural biology clearly paved the way for our understanding of these important antibacterial targets which are also membrane-anchored, a hurdle that has thwarted literally decades of attempts at previous characterization by many groups worldwide." "His protein structure work has shown how Gram positive bacteria synthesize teichoic acids, how bacterial cell walls are transglycosylated, and how enzymes of predatory bacteria partially degrade bacterial cell walls as they invade prey bacteria," explained nominator Liz Sockett, University of Nottingham.

Lovering obtained his B.Sc. in Biochemistry from Birmingham University, where he also earned his Ph.D. in Biosciences. There he used x-ray crystallography to detail the mechanism of action of two enzymes involved in cancer therapies; one a bacterial nitroreductase used in gene therapy of solid tumors, and the other a target for a cell differentiation approach tackling acute myeloid leukemia.

After graduating from Birmingham University, a postdoctoral position in Strynadka's laboratory at the University of British Columbia introduced Lovering to the subject of antibacterial research. This led to determination of the structures of two monotopic membrane proteins involved in bacterial cell wall synthesis. One of these, S. aureus PBP2, represented the first detailed view of how bacteria catalyze the essential step of peptidoglycan polymerisation, a potentially excellent drug target. The other, S. epidermidis TagF, revealed how the Gram-positive wall polymer teichoic acid is synthesized and may form the basis for the development of antivirulents. The PBP2 publication was chosen as one of the highlights of the year by Science and C&E News.

Since establishing his own research group in 2010, Lovering's focus has shifted to deciphering the molecular basis of bacterial predation by Bdellovibrio bacteriovorus, a phenomenon that may lead to its exploitation as a "living antibiotic". In collaboration with Sockett at the University of Nottingham, this approach has already begun to detail how the invading bacterium modifies the prey cell wall for purposes of niche formation, and also how Bdellovibrio and other bacteria hydrolyze the ubiquitous bacterial second messenger cyclic-di-GMP. "As invited speaker of the 2012 Gordon Conference on Bacterial Sensory Transduction, he described the first ever crystal structure of an HD-GYP bacterial signaling protein," says Sockett.

"Lovering's enthusiasm and fascination with the microbial world is always palpable. His level of insight, profound knowledge of fundamental biochemistry, and ability to see connections that others would have missed never fail to amaze me," summarizes Klaus Ftterer, University of Birmingham. "As he builds his research group it is clear that his work will enlighten our understanding of an unusual microorganism, and his enthusiasm will inspire junior researchers in both the structural biology and microbiology communities."

Strynadka agrees, "he is highly collegial, modest, and a natural teacher. His love of and interest in science is truly infectiousknowledge he loves to share with others. Collectively, I believe him to be a truly exceptional rising star who will continue to make fundamental advances to structural microbiology."

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The ICAAC Young Investigator Award will be presented during ASM's 52nd Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), September 9-12, 2012 in San Francisco, CA. ASM is the world's oldest and largest life science organization and has more than 40,000 members worldwide. ASM's mission is to advance the microbiological sciences and promote the use of scientific knowledge for improved health, economic, and environmental well-being.

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The American Society for Microbiology honors Andrew Lovering

Protective bacteria in the infant gut have resourceful way of helping babies break down breast milk

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Public release date: 13-Aug-2012 [ | E-mail | Share ]

Contact: Angela Hopp ahopp@asbmb.org 240-283-6614 American Society for Biochemistry and Molecular Biology

A research team at the University of California, Davis, has found that important and resourceful bacteria in the baby microbiome can ferret out nourishment from a previously unknown source, possibly helping at-risk infants break down components of breast milk.

Breast milk is amazingly intricate, providing all of the nutrients necessary to sustain and strengthen infants in the first months of life. Moreover, this natural source of nutrition provides protection from infections, allergies and many other illnesses.

Breast milk also promotes the growth of protective bacteria in an infant's intestine. Because breast milk contains glycans (complex sugars) that infants cannot breakdown, it promotes the growth a specific type of bacteria, called bifidobacteria, that can process these glycans. While it is known that bifidobacteria avail themselves of the free glycans in breast milk, it was not known whether these bacteria could also obtain glycans that were linked to proteins. Such proteins are called glycoproteins, and they are abundant in breast milk.

The research team led by David A. Mills at the UC-Davis investigated the ability of bifidobacteria to remove glycans from milk glycoproteins. Their work was recently published in the journal Molecular & Cellular Proteomics.

Mills' group found that specific strains of bifidobacteria possessed enzymes capable of removing glycan groups from glycoproteins, enabling them to use these glycans as an additional food source. Surprisingly, one of the enzymes, EndoBI-1, was able to remove any type of N-linked glycan (glycans attached to proteins by the amino acid asparagine). This is unique among enzymes of this type and may provide a growth advantage for bifidobacteria in the infant intestine because the glycoproteins in breast milk have complex glycans attached.

Mills explains that the ability of EndBI-1 to remove a variety of complex N-linked glycans combined with its unusual heat stability make "this potentially a very useful tool in both food processing and proteomics/pharmaceutical research."

The team's work suggests that bifidobacteria do not primarily feed on the glycans from milk glycoproteins. However, the study did show that under the proper conditions bidfidobacteria can grow when protein-linked glycans are the only energy source.

"One obvious goal of this research is to find ways to translate the benefits provided by milk and bifidobacteria to at risk populations such as premature infants, malnourished children, among many others," Mills says.

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Protective bacteria in the infant gut have resourceful way of helping babies break down breast milk

Redskins' Alexander shrinks to play linebacker

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ASHBURN, Va. (AP) -- Lorenzo Alexander has quite a collection of white bottles, labeled with words straight from a biochemistry class. Beta Alanine Supreme. Carnitine Synergy. Uber C. Some 19 containers, big and small, in his Washington Redskins locker.

''I have a lot of supplements,'' he said.

The consummate self-made NFL player, Alexander has always been conscious about his diet. Like many players, he also gets advice on the right mix of tablets to maximize his endurance and energy output. Or, as he puts it, ''to help balance your body out.''

This year, it's been more of a challenge to find that balance. Alexander, who once was a 300-pound lineman, arrived at training camp weighing 245, having dropped some 30 pounds from this time last season so that he can hold his own in his new role as the team's primary backup at inside linebacker.

''Being 265,'' he said, ''is not ideal for covering tight ends and fast wide receivers down the middle of the field.''

No one would expect anything different from the player who arrived as a practice squad nobody in 2006 and soon became an indispensable utility man, working his way up to his current role as a team captain who now gets annual support from his teammates as an ought-to-be Pro Bowl player.

''I'd say he's one of, if not the biggest influence I've had since I've been here,'' said linebacker Ryan Kerrigan, a first-round draft pick last year. ''He seems to me what really embodies a professional. Not just a professional athlete, but a professional human being. He shows you what hard work can do.''

Alexander was a novelty his rookie season, a three-way player who saw game action on the offensive line, defensive line and special teams. He made his name with hard work, smarts and big special teams hits.

In 2010, the Redskins (No. 25 in the AP Pro32) moved him to outside linebacker. Last year, he started learning the inside linebacker position. This year, it's his main focus on the only experienced alternative to starters London Fletcher and Perry Riley in the 3-4 scheme.

Alexander's weight loss has been noticeable during training camp. He broke up a pass over the middle to Santana Moss during Wednesday's practice, the type of play he couldn't have made when he was a lot heavier.

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Redskins' Alexander shrinks to play linebacker

After the Descent: Mars Rover Preps for Thrilling Expedition

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NASA-JPl / Reuters

This artist's concept depicts the moment that NASA's Curiosity rover touches down onto the Martian surface

Barreling in from space at 13,000 mph before stopping a mere 25 feet above the ground would make anyone want to catch their breath, and NASAs Curiosity rover is no exception. Now that the Seven Minutes of Terror is over, the compact-car-sized biochemistry lab is spending its first two weeks doing the same thing you might do after stepping off a hair-raising roller coaster: making sure its parts are where theyre supposed to be and functioning correctly.

That means daily surprises, as technicians at the Jet Propulsion Laboratory in La Canada Flintridge, Calif., raise antennas, activate cameras, and gradually bring systems on line. Among the early treats: 297 black-and-white thumbnail pictures, which NASA processed into a low-quality video showing the final two-and-a-half minutes of Curiositys stomach-churning plunge through the Martian atmosphere. The thumbnails, though grainy, show the protective heat shield dropping away, the bumps from the rovers parachute descent, and dust kicking up as cables lowered the rover to the Martian surface. Scientists expect to have a full-resolution video from Curiositys descent imager in a few days.

(PHOTOS: An Inside Look at the Mars Curiosity Rover)

The rover also sent a new postcard: the first full-color landscape image of Curiositys Gale Crater home, taken as part of a focus test to check one of the cameras mounted on the rovers mast. Until this week the camera, called the Mars Hand Lens Imager (MAHLI),hadnt moved its focal components since July 2011four months before Curiosity launched. Even now, with the mast still tucked horizontally atop the rovers front left shoulder, the cameras initial focus test offers a tempting glimpse of the north wall of the rim at Gale Crater.

But thats just a small taste of what this particular camera, one of 17 aboard Curiosity, will provide once the mast is lifted and extended, especially once the cameras clear dust covers lift away. Its so awesome because we can put this camera anywhere, says Ken Edgett of Malin Space Science Systems in San Diego, which operates the camera. Up, down, within an inch of the soil, underneath the rover, anywhere. Itll extend up above the mast to give us the giraffes-eye view, or give us the oblique, dogs-eye view across the Martian surface. This camera can look wherever we want.

Many of this weeks most captivating images havent come from Curiosity but a high-resolution camera aboard the Mars Reconnaissance Orbiter, another player on NASAs robotic exploration team. One day after capturing a stunning shot of Curiosity parachuting towards Martian surface, the Orbiter executed an unusual 41-degree roll to deliver a fascinating crime scene image taken by a high-resolution camera aboard the Mars Reconnaissance Orbiter some 186 miles above the surface. The view offers a look at the pimple-sized rover in relation to the locations where Curiositys heat shield, parachute, back shell, and ballyhooed sky crane crash-landed after dropping away from the rover during its descent.

(Cover Story: Live From Mars)

Simply put, theyre all in the same Gale Crater neighborhood. The heat shield is farthest from Curiosity, about three-quarters of a mile away. Both the back shell and sky crane wound up about four-tenths of a mile from the rover. Of particular visual interest is a jagged pattern in the Martian soil to one side of the downed sky crane. Those dark areas downrange are the disturbed dust, says Sarah Milkovich, a JPL scientist. Its the same pattern we see when we have meteorites forming impact craters on the surface of a planetary body. Since the impacts from the spacecrafts components kicked up plenty of dust as well, Milkovich says future images should have even greater resolution. The Orbiter will again aim its cameras at Gale Crater in a few days, possibly for color photos.

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After the Descent: Mars Rover Preps for Thrilling Expedition