1.1.1.175 | more |
both D-xylono-gamma-lactone and D-xylonate are produced when the Caulobacter crescentus gene xylB encoding D-xylose dehydrogenase is expressed in Saccharomyces cerevisiae, with or without co-expressionof xylC (D-xylonolactonase). XylC facilitates rapid opening of the lactone and more D-xylonate is initially produced than in its absence. In vivo [1H]NMR analysis of cell extracts, culture media and intact cells is used for analysis. The lactone and linear forms of D-xylonic acid are produced, accumulated intracellularly, and partially exported within 1560 min after D-xylose provision. Co-expression of xylB and xylC leads to rapid loss of pHluorin fluorescence and loss of vitality during production of D-xylonate. Loss of vitality in the presence of D-xylose is correlated to the extracellular pH, but fluorescence is lost from xylB and xylC expressing cells regardless of the extracellular condition. Method optimization, overview |
-, 730321 |