E.i. Dupont De Nemours and Company

Alliance for Sustainable Energy, LLC

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

Midwest Research Institute National Renewable Energy Laboratory Div.

Paul Veikko Viitanen

Perry G Caimi

Luan Tao

Min Zhang

Yat-Chen Chou

Mary Ann Franden

Knut Meyer

Douglas Brian Jordan

Mark Emptage

Yuying Zhang

Carol M McCutchen

Drew E Van Dyk

Karen Onley Bacot

Xu Li

Laura McCole

William Dean Hitz

Dennis Flint

Jean-Francois Tomb

Barry Stieglitz

Jianjun Yang

Min Qi

Kyle Knoke

Carol Mccutchen

Laura Mccole

Carol M Mccutchen

Andrew C Eliot

Fateme Sima Sariaslani

Charles A Omer

Carol M Mc Cutchen

Perry G G Caimi

Onley Bacot Karen

Steven E Buchholz

Robel Y Kahsay

Disrupting expression of a protein encoded by the region of thegenome called ZMO0353 in the genomic sequence of the ZM4 strain was found to improve the use of xylose in a recombinant xylose utilizingcell. In addition, utilization of both xylose and arabinose was improved in a xylose and arabinose utilizingcell with this disruption, and increased ethanol production was achieved.

Enhancing D-xylose and L-arabinose utilization in Zymomonas cells

The endogenous pnp gene encoding polynucleotide phosphorylase in thegenome was identified as a target for modification to provide improved xylose utilizing cells for ethanol production. The cells are in addition genetically modified to have increased expression of ribose-5-phosphate isomerase (RPI) activity, as compared to cells without this genetic modification, and are not limited in xylose isomerase activity in the absence of the pnp modification.

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is unable to synthesize pantothenic acid and requires this essential vitamin in growth medium.strains transformed with an operon for expression of 2-dehydropantoate reductase and aspartate 1-decarboxylase were able to grow in medium lacking pantothenic acid. These strains may be used for ethanol production without pantothenic acid supplementation in seed culture and fermentation media.

Pantothenic acid biosynthesis in zymomonas

Xylose-utilizingstrains studied were found to accumulate ribulose when grown in xylose-containing media. Engineering these strains to increase ribose-5-phosphate isomerase activity led to reduced ribulose accumulation, improved growth, improved xylose utilization, and increased ethanol production.

Xylose utilization in recombinant zymomonas

expressing xylose isomerase fromwas found to have improved xylose utilization, growth, and ethanol production when grown in media containing xylose. Xylose isomerases related to that ofwere identified structurally through molecular phylogenetic and Profile Hidden Markov Model analyses, providing xylose isomerases that may be used to improve xylose utilization.

Xylose-utilizing, ethanol producing strains ofwith improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

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.

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.

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.

Growing community of inventors

West Chester, PA, United States of America

Paul Veikko Viitanen