Hallborn J, Gorwa M F, Meinander N, Penttilä M, Keränen S, Hahn-Hägerdal B
Chemical Centre, Lund University, Sweden.
Appl Microbiol Biotechnol. 1994 Nov;42(2-3):326-33. doi: 10.1007/BF00902737.
Xylitol formation by a recombinant Saccharomyces cerevisiae strain containing the XYL1 gene from Pichia stipitis CBS 6054 was investigated under three sets of conditions: (a) with glucose, ethanol, acetate, or glycerol as cosubstrates, (b) with different oxygenation levels, and (c) with different ratios of xylose to cosubstrate. With both glucose and ethanol the conversion yields were close to 1 g xylitol/g consumed xylose. Decreased aeration increased the xylitol yield on the basis of consumed cosubstrate, while the rate of xylitol formation decreased. The xylitol yield based on consumed cosubstrate also increased with increased-xylose:cosubstrate ratios. The transformant utilized the cosubstrate more efficiently than did a reference strain in terms of utilization rate and growth rate, implying that the regeneration of NAD(P)+ during xylitol formation by the transformant balanced the intracellular redox potential.
在三组条件下研究了含有来自树干毕赤酵母CBS 6054的XYL1基因的重组酿酒酵母菌株形成木糖醇的情况：(a) 以葡萄糖、乙醇、乙酸盐或甘油作为共底物；(b) 不同的氧合水平；(c) 木糖与共底物的不同比例。使用葡萄糖和乙醇时，转化产率均接近1克木糖醇/克消耗的木糖。通气减少会提高基于消耗的共底物的木糖醇产率，而木糖醇形成速率降低。基于消耗的共底物的木糖醇产率也随着木糖:共底物比例的增加而增加。就利用率和生长速率而言，转化体比参考菌株更有效地利用共底物，这意味着转化体在木糖醇形成过程中NAD(P)+的再生平衡了细胞内的氧化还原电位。
