Journal article: http://www.biotechnologyforbiofuels.com/content/6/1/21/abstract

In Singapore, researchers from Nanyang Technological University have introduced molecular pumps into genetically engineered yeast Saccharomyces cerevisiae that allowed it to extrude the alkane that it produced. This mechanism called efflux pump system could alleviate the problem of alkane toxicity in yeast which limits the productivity of yeast-based alkane production system.

Akane is a hydrocarbon component of gasoline fuels that can be biologically produced in microbial hosts like S. cerevisiae but it is known to be toxic to S. cerevisiae. The efflux pump mechanism consisting of two alkane-transporting molecules designated as ABC2 and ABC3 was introduced into S. cerevisiae from a non-conventional species of yeast that can utilize alkanes as carbon source. The engineered yeast cells that expressed and localized ABC2 and ABC3 on their plasma membrane were shown to maintain lower intracellular concentration of alkane chains having 10 carbons (decane) and 11 carbons (undecane). The improved yeast version exhibited over 80-fold increase in the tolerance limit against decane.

The ability to pump out the target alkane products from the cell will not only protect the cell but also increase the final biofuel productivity. Published in the journal Biotechnology for Biofuels, this work was acknowledged by the authors as the first proof of concept for using transport engineering to enhance alkane-producing microbes which will be useful in the production and recovery of next-generation biofuels.

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Journal article (abstract): http://onlinelibrary.wiley.com/doi/10.1111/mec.12230/abstract

Press release: http://www.purdue.edu/newsroom/releases/2013/Q1/understanding-termite-digestion-could-help-biofuels,-insect-control.html

A team of scientists who have been studying the digestive system of the termite insect and the microorganisms living in its gut have found new evidence that may allow them to track down the genes involved in the breakdown of lignin, the tough material in plant cell wall that inhibits the conversion of its starch into sugars destined for fermentation into biofuel.

The Purdue University has reported the work of its leading entomologist and his collaborators who have been studying the termite's symbionts or microorganisms that live in its gut and aid in wood digestion. Initially the scientists focused on symbiotic bacteria but recent results of their study suggest that other groups of symbionts are helping the insect to degrade wood. When the termites were fed diets of wood or paper, the composition of bacterial population in the insect's gut was unchanged, suggesting that bacteria probably do not have anything to do with wood digestion. Instead they found that the genes expressed by the host termite and another group of symbionts called protists showed more significant changes in response to diet shift.

About 500 genes from the host termite and symbiotic protists responded to lignin-rich diets, which the scientists now see as potential genes involved in lignin breakdown. Tracking down and understanding these genes may lead to a new breakthrough in enzyme discovery toward more efficient production of second generation and advanced biofuels. The most recent scientific article that described this finding is published in the journal Molecular Ecology.

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Journal article (abstract): http://www.nature.com/nbt/journal/vaop/ncurrent/full/nbt.2509.html

Press release: http://web.mit.edu/newsoffice/2013/yeast-research-may-boost-biofuel-production-efficiency-0217.html

Scientists at the Massachusetts Institute of Technology (MIT) have increased the amount of isobutanol manufactured by yeast through restricting the entire production process within the cell organelles called mitochondria.

During fermentation, yeast cells can make small amount of isobutanol, an alcohol that contains more energy than ethanol and is more suitable as a transport biofuel. The natural production process for isobutanol in yeast consists of stages that are compartmentalized in the mitochondria and cytoplasm of the cell. A precursor called pyruvate, a product from sugar breakdown, is first transported from cytoplasm into mitochondria where it is converted into an intermediate. This intermediate is transported back to the cytoplasm where it is converted by a set of enzymes into isobutanol. Getting all the enzymes to function only in the cytoplasm is not an easy feat and isobutanol yield by this approach was shown to be very low.

When the MIT researchers took the opposite approach – moving the cytoplasmic phase into the mitochondria and confining the process within this organelle – isobutanol yield increased by 260%. The team accomplished this by engineering the enzymes such that they each had a protein tag that identified them as destined for mitochondria. According to the report published in Nature Biotechnology, the compartmentalization had likely enhanced the process through greater local enzyme concentrations, increased availability of intermediates and reduced losses of intermediates as they are transported out of mitochondria.

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Journal article: http://www.eurekaselect.com/107068/article

Indian researchers reported in the journal Recent Patents on DNA and Gene Sequences an application of patent analytics as tool to track the technological trend in biofuels research and development.

A marked increase in the number of published patents related to the application of genetic engineering for biofuel development has been noted in the past 2 to 3 years. Data mining through a set of 1243 patent documents related to transgenic technology for biofuel production generated a theme map that helped the researchers to visualize the trends and relationships within the patent landscape. The researchers analyzed within a conceptualized framework the trends in transgene application, feedstock development and the processes used to generate the various bioenergy products.

A detailed analysis of patent claims showed highest interest in biofuel source followed by feedstock component wherein 27 percent of patents for whole organisms cover major biofuel crops and microorganisms. Patents for biofuel sources primarily cover microorganism (45%) and oil crops (33%) and only 8% cover sugar and grain crops, indicating an emphasis on exploring non-food bioresources for biofuels production.

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News article: http://www.ethanolproducer.com/articles/9576/canadian-government-invests-in-biofuel-initiatives

News article: : http://www.biofuelsjournal.com/articles/Canada_Funds_Sugar_Beet_Biofuel_Research-130391.html

An investment worth $600,000 from the Canadian government will fund projects that will benefit local biofuel and biorefining industries. The fund is intended to help the Alberta Sugar Beets Growers to study the use of sugar beets and energy beets as feedstock for the production of bio-butanol, a promising biofuel that can run current gasoline engines, and bio-glycol, a renewable alternative to petrochemicals that can serve as precursor for a variety of products such as plastics, polyester fiber and resin. The fund, supported through the Canadian Agricultural Adaptation Program, will also be used to provide business advice for the commercialization of the beet-based renewable products.