In recombinant, xylose-fermenting Saccharomyces cerevisiae, about 30% of the consumed xylose is converted to xylitol. Xylitol production results from a cofactor imbalance, since xylose reductase uses both NADPH and NADH, while xylitol dehydrogenase uses only NAD(+). In this study we increased the ethanol yield and decreased the xylitol yield by lowering the flux through the NADPH-producing pent...

Diglycerol phosphate accumulates under salt stress in the archaeon Archaeoglobus fulgidus (L. O. Martins, R. Huber, H. Huber, K. O. Stetter, M. S. da Costa, and H. Santos, Appl. Environ. Microbiol. 63:896-902, 1997). This solute was purified after extraction from the cell biomass. In addition, the optically active and the optically inactive (racemic) forms of the compound were synthesized, and ...

The pathway of carbohydrate degradation, which begins with the action of G-6-P dehydrogenase’ on G-6-P, has been studied by a number of workers (l-9). Their results have shown the operation of this scheme in a variety of tissues (yeast, red blood cells, and mammalian liver). The existence of G-6-P dehydrogenase in various seeds (10) suggests the occurrence of this system in higher plants. The p...

e.g. phosphoglucomutase, glucose 6-phosphate dehydrogenase and fructose 6-phosphate kinase. However, if the reaction occurs distant from the anomeric carbon atom of the substrate the enzymes show no anomeric specificity, e.g. hexokinase, glucokinase and glucose 6-phosphatase (Wurster & Hess, 1974~). A search for enzymes catalysing anomerization reactions leads to the following conclusion. For D...

1. A method is described for extracting separately mitochondrial and extramitochondrial enzymes from fat-cells prepared by collagenase digestion from rat epididymal fat-pads. The following distribution of enzymes has been observed (with the total activities of the enzymes as units/mg of fat-cell DNA at 25°C given in parenthesis). Exclusively mitochondrial enzymes: glutamate dehydrogenase (1.8),...