Metabolic engineering of Saccharomyces cerevisiae for bioconversion of D-xylose to D-xylonate
메타 데이터
바이오화학분류
바이오플라스틱
기타
바이오정밀화학
기타
화장품용 기능성소재
기타
의료용 화학소재
식품첨가제
논문
Metabolic engineering of Saccharomyces cerevisiae for bioconversion of D-xylose to D-xylonate
학술지
Metabolic engineering
저자명
Toivari, M.; Nygard, Y.; Kumpula, E.P.; Vehkomaki, M.L.; Bencina, M.; Valkonen, M.; Maaheimo, H.; Andberg, M.; Koivula, A.; Ruohonen, L.; Penttila, M.; Wiebe, M.G.
초록
An NAD<SUP>+</SUP>-dependent d-xylose dehydrogenase, XylB, from Caulobacter crescentus was expressed in Saccharomyces cerevisiae, resulting in production of 17+/-2g d-xylonate l<SUP>-1</SUP> at 0.23gl<SUP>-1</SUP>h<SUP>-1</SUP> from 23g d-xylose l<SUP>-1</SUP> (with glucose and ethanol as co-substrates). d-Xylonate titre and production rate were increased and xylitol production decreased, compared to strains expressing genes encoding T. reesei or pig liver NADP<SUP>+</SUP>-dependent d-xylose dehydrogenases. d-Xylonate accumulated intracellularly to ∼70mgg<SUP>-1</SUP>; xylitol to ∼18mgg<SUP>-1</SUP>. The aldose reductase encoding gene GRE3 was deleted to reduce xylitol production. Cells expressing d-xylonolactone lactonase xylC from C. crescentus with xylB initially produced more extracellular d-xylonate than cells lacking xylC at both pH 5.5 and pH 3, and sustained higher production at pH 3. Cell vitality and viability decreased during d-xylonate production at pH 3.0. An industrial S. cerevisiae strain expressing xylB efficiently produced 43g d-xylonate l<SUP>-1</SUP> from 49g d-xylose l<SUP>-1</SUP>1.