Metabolic engineering of Caldicellulosiruptor bescii yields increased hydrogen production from lignocellulosic biomass

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Background:
Members of the anaerobic thermophilic bacterial genus Caldicellulosiruptor are emerging candidates for consolidated bioprocessing (CBP) because they are capable of efficiently growing on biomass without conventional pretreatment. C. bescii produces primarily lactate, acetate and hydrogen as fermentation products, and while some Caldicellulosiruptor strains produce small amounts of ethanol C. bescii does not, making it an attractive background to examine the effects of metabolic engineering. The recent development of methods for genetic manipulation has set the stage for rational engineering of this genus for improved biofuel production. Here, we report the first targeted gene deletion, the gene encoding lactate dehydrogenase (ldh), for metabolic engineering of a member of this genus.
Results:
A deletion of the C. bescii L-lactate dehydrogenase gene (ldh) was constructed on a non-replicating plasmid and introduced into the C. bescii chromosome by marker replacement. The resulting strain failed to produce detectable levels of lactate from cellobiose and maltose, instead increasing production of acetate and H2 by 21-34% relative to the wild type and ?pyrFA parent strains. The same phenotype was observed on a real-world substrate – switchgrass (Panicum virgatum). Furthermore, the ldh deletion strain grew to a higher maximum optical density than the wild type on maltose and cellobiose, consistent with the prediction that the mutant would gain additional ATP with increased acetate production.
Conclusions:
Deletion of ldh in C. bescii is the first use of recently developed genetic methods for metabolic engineering of these bacteria. This deletion resulted in a redirection of electron flow from production of lactate to acetate and hydrogen. New capabilities in metabolic engineering combined with intrinsic utilization of lignocellulosic materials position these organisms to provide a new paradigm for consolidated bioprocessing of fuels and other products from biomass.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/85

Growth and fermentation of D-xylose by Saccharomyces cerevisiae expressing a novel D-xylose isomerase originating from the bacterium Prevotella ruminicola TC2-24

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Background:
Saccharomyces cerevisiae strains expressing D-xylose isomerase (XI) produce some of the highest reported ethanol yields from D-xylose. Unfortunately, most bacterial XIs that have been expressed in S. cerevisiae are either not functional, require additional strain modification, or have low affinity for D-xylose. This study analyzed several XIs from rumen and intestinal microorganisms to identify enzymes with improved properties for engineering S. cerevisiae for D-xylose fermentation.
Results:
Four XIs originating from rumen and intestinal bacteria were isolated and expressed in a S. cerevisiae CEN.PK2-1C parental strain primed for D-xylose metabolism by over expression of its native D-xylulokinase. Three of the XIs were functional in S. cerevisiae, based on the strain's ability to grow in D-xylose medium. The most promising strain, expressing the XI mined from Prevotella ruminicola TC2-24, was further adapted for aerobic and fermentative growth by serial transfers of D-xylose cultures under aerobic, and followed by microaerobic conditions. The evolved strain had a specific growth rate of 0.23 h-1 on D-xylose medium, which is comparable to the best reported results for analogous S. cerevisiae strains including those expressing the Piromyces sp. E2 XI. When used to ferment D-xylose, the adapted strain produced 13.6 g/L ethanol in 91 h with a metabolic yield of 83% of theoretical. From analysis of the P. ruminicola XI, it was determined the enzyme possessed a Vmax of 0.81 mumole/min/mg protein and a Km of 34 mM.
Conclusion:
This study identifies a new xylose isomerase from the rumen bacterium Prevotella ruminicola TC2-24 that has one of the highest affinities and specific activities compared to other bacterial and fungal D-xylose isomerases expressed in yeast. When expressed in S. cerevisiae and used to ferment D-xylose, very high ethanol yield was obtained. This new XI should be a promising resource for constructing other D-xylose fermenting strains, including industrial yeast genetic backgrounds.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/84

How good to use home pregnancy tests

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Home pregnancy tests have been practiced for long by women and is quite trusted way of confirming your doubts when it comes to conceiving. Here are certain signs that can tell you that you are probably pregnant.

If you have missed your period or you are having an abnormal or unusual period may be you are pregnant. If you have got frequent urinating tendencies or you throw up (vomit) again and again it is possible that you are pregnant. Generally women tend to lose their control over bladder when pregnant; it is very hard to control excretion of urine. Morning sickness or nausea is a tendency that is observed in pregnant women. They cannot resist throwing up again and again during the second and third months of pregnancy. Enlargement or soreness in breast is also indicates that possibly you are pregnant. Breast starts to grow big and become painful. If your breast is releasing colostrums, uterus is enlarged or you are getting a lot of stretch marks there is a possibility that you may be pregnant. In case you have frequent strange cravings like you have never had in past may be a n indication that you are pregnant.

However, these are not confirmed signs of pregnancy. Some of these symptoms when experienced together increase the probability of one’s pregnancy. You should immediately rush for a pregnancy test if you are even a little doubtful. This will clarify your doubts as it is a reliable way to test your pregnancy by yourself. You can also trace the pregnancy by an ultrasound test but home pregnancy strip test is more handy, cheap and reliable.

In case you are planning to conceive these are some symptoms that might be pointing towards your positive result on a pregnancy strip. Be happy you are experiencing such phenomenon and consult a doctor as soon as possible. Apart from all this reflect on your inner sight you can feel it when you are pregnant and the tests suggested above are just a primary confirmation.

In case you do not want to bear there are ways to get out of the web. Contraceptive pills are available in the market which can be a help in forbidding any pregnancy. There are pills that you can take within 72 hours after having unprotected sex to prevent pregnancy but its intake again and again can cause side effects. If you detect a positive on the pregnancy strip, you will have to abort it whether it is by an abortion pill or by any other method.

About The Author: Camila is a writer/blogger. She loves writing, traveling and reading books. She contributes on Josh Fink

Source:
http://www.biotechblog.org/entry/good-home-pregnancy-tests/

Overcoming restriction as a barrier to DNA transformation in Caldicellulosiruptor species results in efficient marker replacement

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Background:
Thermophilic microorganisms have special advantages for the conversion of plant biomass to fuels and chemicals. Members of the genus Caldicellulosiruptor are the most thermophilic cellulolytic bacteria known. They have the ability to grow on a variety of non-pretreated biomass substrates at or near ~80 C and hold promise for converting biomass to bioproducts in a single step. As for all such relatively uncharacterized organisms with desirable traits, the ability to genetically manipulate them is a prerequisite for making them useful. Metabolic engineering of pathways for product synthesis is relatively simple compared to engineering the ability to utilize non-pretreated biomass.
Results:
Here we report the construction of a deletion of cbeI (Cbes2438), which encodes a restriction endonuclease that is as a major barrier to DNA transformation of C. bescii. This is the first example of a targeted chromosomal deletion generated by homologous recombination in this genus and the resulting mutant, JWCB018 (DeltapyrFA DeltacbeI), is readily transformed by DNA isolated from E. coli without in vitro methylation. PCR amplification and sequencing suggested that this deletion left the adjacent methyltransferase (Cbes2437) intact. This was confirmed by the fact that DNA isolated from JWCB018 was protected from digestion by CbeI and HaeIII. Plasmid DNA isolated from C. hydrothermalis transformants were readily transformed into C. bescii. Digestion analysis of chromosomal DNA isolated from seven Caldicellulosiruptor species by using nine different restriction endonucleases was also performed to identify the functional restriction-modification activities in this genus.
Conclusion:
Deletion of the cbeI gene removes a substantial barrier to routine DNA transformation and chromosomal modification of C. bescii. This will facilitate the functional analyses of genes as well as metabolic engineering for the production of biofuels and bioproducts from biomass. An analysis of restriction-modification activities in members of this genus suggests a way forward to eliminating restriction as a barrier to DNA transformation and efficient genetic manipulation of this important group of hyperthermophiles.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/82

Effect of salts on the Co-fermentation of glucose and xylose by a genetically engineered strain of Saccharomyces cerevisiae

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Background:
A challenge currently facing the cellulosic biofuel industry is the efficient fermentation of both C5 and C6 sugars in the presence of inhibitors. To overcome this challenge, microorganisms that are capable of mixed-sugar fermentation need to be further developed for increased inhibitor tolerance. However, this requires an understanding of the physiological impact of inhibitors on the microorganism. This paper investigates the effect of salts on Saccharomyces cerevisiae 424A(LNH-ST), a yeast strain capable of effectively co-fermenting glucose and xylose.
Results:
In this study, we show that salts can be significant inhibitors of S. cerevisiae. All 6 pairs of anions (chloride and sulfate) and cations (sodium, potassium, and ammonium) tested resulted in reduced cell growth rate, glucose consumption rate, and ethanol production rate. In addition, the data showed that the xylose consumption is more strongly affected by salts than glucose consumption at all concentrations. At a NaCl concentration of 0.5M, the xylose consumption rate was reduced by 64.5% compared to the control. A metabolomics study found a shift in metabolism to increased glycerol production during xylose fermentation when salt was present, which was confirmed by an increase in extracellular glycerol titers by 4 fold. There were significant differences between the different cations. The salts with potassium cations were the least inhibitory. Surprisingly, although salts of sulfate produced twice the concentration of cations as compared to salts of chloride, the degree of inhibition was the same with one exception. Potassium salts of sulfate were less inhibitory than potassium paired with chloride, suggesting that chloride is more inhibitory than sulfate.
Conclusions:
When developing microorganisms and processes for cellulosic ethanol production, it is important to consider salt concentrations as it has a significant negative impact on yeast performance, especially with regards to xylose fermentation.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/83

Puma Biotechnology Receives US FDA Approval of Supplemental New Drug Application for Neratinib to Treat HER2-Positive Metastatic Breast Cancer -…

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Feb. 26, 2020 13:03 UTC

LOS ANGELES--(BUSINESS WIRE)--Puma Biotechnology. (NASDAQ: PBYI), a biopharmaceutical company, announced that the U.S. Food and Drug Administration (FDA) approved a supplemental New Drug Application (sNDA) for neratinib in combination with capecitabine for the treatment of adult patients with advanced or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in the metastatic setting. The sNDA approval was based on results of the Phase III NALA trial, a randomized controlled trial of neratinib plus capecitabine in patients with HER2-positive metastatic breast cancer who have received two or more prior anti-HER2-based regimens.

Although there have been many new treatment options for patients with HER2-positive breast cancer, patients still need additional treatment options once they progress, said Alan H. Auerbach, Chief Executive Officer and President of Puma. Based on the results of our NALA data, we believe NERLYNX could be a promising therapeutic opportunity for these patients.

Adam M. Brufsky, MD, Ph.D., of Magee-Womens Hospital and the Hillman Cancer Center at the University of Pittsburgh Medical Center, added, Together with the NALA investigators around the world, I am pleased to see the FDA approval of NERLYNX for the treatment of advanced HER2-positive metastatic breast cancer. This approval is based on data from the NALA trial, which we presented at ASCO last year, demonstrating that neratinib in combination with capecitabine offers a significant improvement over currently available therapies in this heavily pretreated patient population and can be added to NERLYNXs established role in the treatment of early breast cancer.

In the United States, NERLYNX is approved for the extended adjuvant treatment of adult patients with early stage HER2-positive breast cancer, following adjuvant trastuzumab-based therapy. In Europe, NERLYNX is approved for the extended adjuvant treatment of adult patients with early stage hormone receptor-positive HER2-overexpressed/amplified breast cancer and who are less than one year from completion of prior adjuvant trastuzumab-based therapy. NERLYNX has also received approval for use in the extended adjuvant setting in Canada, Australia, Hong Kong, Singapore and Argentina.

In collaboration with its global licensing partners, Puma expects to seek approval of this second indication in all countries where NERLYNX is currently approved.

About NALA

Efficacy of neratinib in combination with capecitabine was investigated in NALA (NCT01808573), a randomized, multicenter, open-label, Phase III clinical trial in 621 patients with metastatic HER2-positive breast cancer who received two or more prior anti-HER2-based regimens in the metastatic setting. Patients were randomized (1:1) to receive neratinib 240 mg orally once daily on days 1-21 in combination with capecitabine 750 mg/m2 given orally twice daily on days 1-14 for each 21-day cycle (n=307) or lapatinib 1250 mg orally once daily on days 1-21 in combination with capecitabine 1000 mg/m2 given orally twice daily on days 1-14 for each 21-day cycle (n=314). Patients were treated until disease progression or unacceptable toxicity. The trial was conducted globally at sites in North America, Europe, Israel, Asia-Pacific and South America.

The main efficacy outcome measures were progression-free survival (PFS) as assessed by a blinded independent central review per RECIST v1.1 and overall survival (OS). Key secondary outcome measures were objective response rate (ORR) and duration of response (DOR). Treatment with neratinib in combination with capecitabine resulted in a statistically significant improvement in PFS (Hazard Ratio 0.76; 95% CI: 0.63, 0.93; p=0.0059) compared to treatment with lapatinib plus capecitabine. The PFS rate at 12 months was 29% (95% CI: 23, 35) for patients who received neratinib plus capecitabine vs 15% (95% CI: 10, 20) for patients who received lapatinib plus capecitabine; the PFS rate at 24 months was 12% (95% CI: 7, 18) vs 3% (95% CI: 1, 8), respectively.

Median OS was 21 months (95% CI: 17.7, 23.8) for patients who received neratinib in combination with capecitabine compared to 18.7 months (95% CI: 15.5, 21.2) for patients who received lapatinib in combination plus capecitabine (HR 0.88; 95% CI: 0.72, 1.07; p=0.2086). The ORR was 32.8% (95% CI: 27.1, 38.9) vs 26.7% (95% CI: 21.5, 32.4), respectively. Median duration of response was 8.5 months (95% CI: 5.6, 11.2) vs 5.6 months (95% CI: 4.2, 6.4), respectively.

The most common adverse reactions of any grade (>5%) in the neratinib plus capecitabine arm were diarrhea, nausea, vomiting, decreased appetite, constipation, fatigue/asthenia, weight decreased, dizziness, back pain, arthralgia, urinary tract infection, upper respiratory tract infection, abdominal distention, renal impairment, and muscle spasms. The most frequently reported Grade 3 or 4 adverse reactions were diarrhea, nausea, vomiting, fatigue and decreased appetite.

The recommended neratinib dose for advanced or metastatic breast cancer is 240 mg (6 tablets) given orally once daily with food on days 1-21 of a 21-day cycle plus capecitabine (750 mg/m2 given orally twice daily) on days 1-14 of a 21-day cycle until disease progression or unacceptable toxicities.

About HER2-Positive Breast Cancer

Approximately 20% to 25% of breast cancer tumors over-express the HER2 protein. HER2-positive breast cancer is often more aggressive than other types of breast cancer, increasing the risk of disease progression and death. Although research has shown that trastuzumab can reduce the risk of early stage HER2-positive breast cancer returning after surgery, up to 25% of patients treated with trastuzumab experience recurrence.

IMPORTANT SAFETY INFORMATION

NERLYNX (neratinib) tablets, for oral use

INDICATIONS AND USAGE: NERLYNX is a kinase inhibitor indicated:

CONTRAINDICATIONS: None

WARNINGS AND PRECAUTIONS:

ADVERSE REACTIONS:

The most common adverse reactions (reported in 5% of patients) were as follows:

To report SUSPECTED ADVERSE REACTIONS, contact Puma Biotechnology, Inc. at 1-844-NERLYNX (1-844-637-5969) and http://www.NERLYNX.com or FDA at 1-800-FDA-1088 or http://www.fda.gov/medwatch.

DRUG INTERACTIONS:

USE IN SPECIFIC POPULATIONS:

Please see Full Prescribing Information for additional safety information.

To help ensure patients have access to NERLYNX, Puma has implemented the Puma Patient Lynx support program to assist patients and healthcare providers with reimbursement support and referrals to resources that can help with financial assistance. More information on the Puma Patient Lynx program can be found at http://www.NERLYNX.com or 1-855-816-5421.

About Puma Biotechnology

Puma Biotechnology, Inc. is a biopharmaceutical company with a focus on the development and commercialization of innovative products to enhance cancer care. Puma in-licenses the global development and commercialization rights to PB272 (neratinib, oral), PB272 (neratinib, intravenous) and PB357. Neratinib, oral was approved by the U.S. Food and Drug Administration in 2017 for the extended adjuvant treatment of adult patients with early stage HER2-overexpressed/amplified breast cancer, following adjuvant trastuzumab-based therapy and is marketed in the United States as NERLYNX (neratinib) tablets. NERLYNX was granted marketing authorization by the European Commission in 2018 for the extended adjuvant treatment of adult patients with early stage hormone receptor-positive HER2-overexpressed/amplified breast cancer and who are less than one year from completion of prior adjuvant trastuzumab-based therapy. NERLYNX is a registered trademark of Puma Biotechnology, Inc.

Forward-Looking Statements

This news release includes forward-looking statements. All forward-looking statements involve risks and uncertainties that could cause actual results to differ materially from the anticipated results and expectations expressed in these forward-looking statements. These statements are based on current expectations, forecasts and assumptions, and actual outcomes and results could differ materially from these statements due to a number of factors, which include, but are not limited to, the risk factors disclosed in the periodic and current reports filed by Puma with the Securities and Exchange Commission from time to time, including, once filed, Pumas Annual Report on Form 10-K for the year ended December 31, 2019. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. Puma assumes no obligation to update these forward-looking statements, except as required by law.

View source version on businesswire.com: https://www.businesswire.com/news/home/20200226005248/en/

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Puma Biotechnology Receives US FDA Approval of Supplemental New Drug Application for Neratinib to Treat HER2-Positive Metastatic Breast Cancer -...

2013StanfordE25B: A View of How Material Science And Engineering is Transforming Biotechnology – Video

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2013StanfordE25B: A View of How Material Science And Engineering is Transforming Biotechnology
Project Authors: Dieter Rutzen and Sara Rodriguez We interviewed Prof. Nick Melosh from the Department of Material Science and Engineering in Stanford Univer...

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2013StanfordE25B: A View of How Material Science And Engineering is Transforming Biotechnology - Video

Biotechnology | Degree Programs

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Associate of Applied Science Advising Code: A 20 10 0

Contact: (336) 334-4822, ext. 50357

The Biotechnology curriculum is designed to meet the increasing demands for skilled laboratory technicians in various fields of biological and chemical technology.

Course work emphasizes biology, chemistry, mathematics and technical communications. The curriculum objectives are designed to prepare graduates to serve in three distinct capacities: research assistant to a biologist or chemist; laboratory technician/ instrumentation technician; and quality control/quality assurance technician.

Graduates may find employment in various areas of industry and government including research and development, manufacturing, sales, and customer service.

The Biotechnology Program at GTCC is a collaborative educational program offered by Alamance Community College (ACC) and GTCC. Students are able to complete the first two semesters, as well as some selected general education courses from the second year, at GTCC. Students who successfully complete at least the first two semesters at GTCC will be admitted to the Alamance Community College program and will be able to complete the program requirements at ACC. Alamance Community College will award the Associate of Applied Science degree to all students who meet degree requirements.

Program Outcomes:

Additional Biology courses including BIO 250 Genetics and BIO 275 Microbiology can be taken at GTCC for credit at ACC.

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Biotechnology | Degree Programs