Alliance for Sustainable Energy, LLC

Midwest Research Institute

E.i. Dupont De Nemours and Company

E.i. Du Pont De Nemours and Company Alliance for Sustainable Energy LLC

Midwest Research Institute National Renewable Energy Laboratory Div.

Min Zhang

Yat-Chen Chou

Mary Ann Franden

Paul Veikko Viitanen

Perry G Caimi

Stephen K Picataggio

Luan Tao

Mark Emptage

Eric P Knoshaug

Arjun Singh

Yuying Zhang

Carol M McCutchen

Mark Finkelstein

Pirkko Suominen

Eric E Jarvis

Xu Li

Kristine A Deanda

Christina K Eddy

Ali Mohagheghi

Laura McCole

Kyle Knoke

Michael E Himmel

Jeffrey G Linger

Michael T Guarnieri

Philip Thomas Pienkos

Kent Evans

Mildred M Newman

James D McMillan

Carol M Mc Cutchen

William Howe

Shihui Yang

Christine Eddy

James D Mc Millan

Carol Mccutchen

Non-naturally occurringstrains useful for the production of 2,3-butanediol are provided.

Engineered zymomonas for the production of 2,3-butanediol

Presented herein are oleaginous strains of yeast such asthat have been modified to allow for xylose utilization. Such strains are also modified to allow for higher lipid accumulation utilizing a broad range of sugar monomers such as those released during pretreatment and enzymatic saccharification of lignocellulosic biomass. Methods of producing lipids and ethanol using these yeast strains are also disclosed.

Xylose utilizing oleaginous yeast

Disclosed herein are biocatalysts for the production of biofuels, including microorganisms that contain genetic modifications conferring tolerance to growth and fermentation inhibitors found in many cellulosic feedstocks. Methods of converting cellulose-containing materials to fuels and chemicals, as well as methods of fermenting sugars to fuels and chemicals, using these biocatalysts are also disclosed.

Biocatalysts with enhanced inhibitor tolerance

An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

L-arabinose fermenting yeast

Strains of xylose utilizingwith improved xylose utilization and ethanol production during fermentation in stress conditions were obtained using an adaptation method. The adaptation involved continuously growing xylose utilizingin media containing high sugars, acetic acid, ammonia, and ethanol.

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Strains ofwere engineered by introducing a chimeric xylose isomerase gene that contains a mutant promoter of theglyceraldehyde-3-phosphate dehydrogenase gene. The promoter directs increased expression of xylose isomerase, and when the strain is in addition engineered for expression of xylulokinase, transaldolase and transketolase, improved utilization of xylose is obtained.

Zymomonas with improved xylose utilization

Identified are mutants of the promoter of theglyceraldehyde-3-phosphate dehydrogenase gene, which direct improved expression levels of operably linked heterologous nucleic acids. These are high expression promoters useful for expression of chimeric genes in, and other related bacteria.

Through screening of amutant library the himA gene was found to be involved in the inhibitory effect of acetate onperformance. Xylose-utilizingstrains further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in mixed-sugars medium comprising xylose, and, in particular, in the presence of acetate.

An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. Methods of producing ethanol include utilizing these modified yeast strains. 

Through screening of amutant library the himA gene was found to be involved in the inhibitory effect of acetate onperformance. Xylose-utilizingfurther engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in medium comprising xylose and acetate.

Production of ethanol using a strain of xylose-utilizingwith a genetic modification of the glucose-fructose oxidoreductase gene was found to be improved due to greatly reduced production of xylitol, a detrimental by-product of xylose metabolism synthesized during fermentation.

Ethanol production using xylitol synthesis mutant of xylose-utilizing zymomonas

A strain of xylose-utilizingwas engineered with a genetic modification to the glucose-fructose oxidoreductase gene resulting in reduced expression of GFOR enzyme activity. The engineered strain exhibits reduced production of xylitol, a detrimental by-product of xylose metabolism. It also consumes more xylose and produces more ethanol during mixed sugar fermentation under process-relevant conditions.

Xylitol synthesis mutant of xylose-utilizing zymomonas for ethanol production

Xylose-utilizingstrains were found to have improved ethanol production when grown in medium containing mixed sugars including xylose if sorbitol or mannitol was included in the medium. The effect was seen in concentrations of mixed sugars where no growth lag period occurs, as well as in higher sugars concentrations.

Growing community of inventors

Lakewood, CO, United States of America

Min Zhang