Cloning of the Xylitol Dehydrogenase Gene from Glticonobacter oxydans and Improved Production of Xylitol from D

sequence suggested that the enzyme belongs to the short-chain dehydrogenase!reductase family. Expression plasmids for the xith gene were constructed and used to produce recombinant strains of G. orvdans that had up to 11-fold greater XDH actiyity than the wildtype strain. When used in the pToduction of xylitol from D-arabitol under controlled aeration and pH conditions, the strain harboring the xdh expression plasmids produced 57 gfl xylito] from 225 gf) D-arabitol, whereas the control strain produced 27g!1 xylitol. These results demonstrated that increasing XDH activity in G. orydans improyed xylitol productiyity.