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.

Original post:
Local Weather

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).

See more here:
‘Promiscuous’ enzymes still common in metabolism

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.

Read more:
NDSU Research Connects the Dots to Renewable Energy Future

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.

Read the original here:
'Promiscuous' enzymes still prevalent in metabolism

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.

Here is the original post:
Science Study Shows 'Promiscuous' Enzymes Still Prevalent in Metabolism

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