Xylitol production by a Pichia stipitis D-xylulokinase mutant.
Xylitol production by Pichia stipitis FPL-YS30, a xyl3-delta1 mutant that metabolizes xylose using an alternative metabolic pathway, was investigated under aerobic and oxygen-limited culture conditions. Under both culture conditions, FPL-YS30 (xyl3-delta1) produced a negligible amount of ethanol and converted xylose mainly into xylitol with comparable yields (0.30 and 0.27 g xylitol/g xylose). However, xylose consumption increased five-fold under aerobic compared to oxygen-limited conditions. This suggests that the efficiency of the alternative route of xylose assimilation is affected by respiration. As a result, the FPL-YS30 strain produced 26 g/l of xylitol, and exhibited a higher volumetric productivity (0.22 g xylitol l(-1) h(-1)) under aerobic conditions.
Jin
Yong-Su
YS
Department of Food Science, University of Wisconsin-Madison, 1550 Linden Drive, Madison, WI 53706, USA.
Cruz
Jose
J
Jeffries
Thomas W
TW
D005285:Fermentation; D009154:Mutation; D010101:Oxygen Consumption; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics* / Q000378:metabolism*; D010843:Pichia / Q000201:enzymology* / Q000235:genetics*; D013997:Time Factors; D014993:Xylitol / Q000096:biosynthesis*; D014994:Xylose / Q000378:metabolism
D014994:Xylose; D017853:Phosphotransferases (Alcohol Group Acceptor); C032700:xylulokinase; D014993:Xylitol