Metabolic engineering for improved microbial pentose fermentation

Metabolic engineering for improved microbial pentose fermentation.

Global concern over the depletion of fossil fuel reserves, and the detrimental impact that combustion of these materials has on the environment, is focusing attention on initiatives to create sustainable approaches for the production and use of biofuels from various biomass substrates. The development of a low-cost, safe and eco-friendly process for the utilization of renewable resources to gen...

Metabolic engineering for improved fermentation of pentoses by yeasts

The fermentation of xylose is essential for the bioconversion of lignocellulose to fuels and chemicals, but wild-type strains of Saccharomyces cerevisiae do not metabolize xylose, so researchers have engineered xylose metabolism in this yeast. Glucose transporters mediate xylose uptake, but no transporter specific for xylose has yet been identified. Over-expressing genes for aldose (xylose) red...

Engineering redox cofactor regeneration for improved pentose fermentation in Saccharomyces cerevisiae.

Pentose fermentation to ethanol with recombinant Saccharomyces cerevisiae is slow and has a low yield. A likely reason for this is that the catabolism of the pentoses D-xylose and L-arabinose through the corresponding fungal pathways creates an imbalance of redox cofactors. The process, although redox neutral, requires NADPH and NAD+, which have to be regenerated in separate processes. NADPH is...

Pentose Fermentation by Lactobacillus Plantarum

Extracts of Lactobucillus plantarum derived from cells grown on Larabinose contain an active isomerase, which converts L-arabinose to Lribulose (1, 2), and a ribulokinase, which catalyzes the formation of L-ribulose &phosphate (3,4). Such extracts also catalyze the conversion of L-ribulose 5-phosphate to D-xylulose 5-phosphate, which has been shown to be the key intermediate in pentose fermenta...

Synthetic Carbon Fixation for Improved Microbial Fermentation Yields