AUTHOR=Wen Xin , Lin Huibin , Ning Yuhang , Liu Guangwen , Ren Yilin , Li Can , Zhang Chengjia , Lin Jianqun , Song Xin , Lin Jianqiang 

TITLE=D-Allulose (D-Psicose) Biotransformation From Allitol by a Newly Found NAD(P)-Dependent Alcohol Dehydrogenase From Gluconobacter frateurii NBRC 3264 and the Enzyme Characterization

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.870168

DOI=10.3389/fmicb.2022.870168

ISSN=1664-302X

ABSTRACT=<p>The NAD(P)-dependent alcohol dehydrogenase (ADH) gene was cloned from <italic>Gluconobacter frateurii</italic> NBRC 3264 and expressed in <italic>Escherichia coli</italic> BL21 star (DE3). The expressed enzyme was purified and the characteristics were investigated. The results showed that this ADH can convert allitol into <sc>D</sc>-allulose (<sc>D</sc>-psicose), which is the first reported enzyme with this catalytic ability. The optimum temperature and pH of this enzyme were 50°C and pH 7.0, respectively, and the enzyme showed a maximal activity in the presence of Co<sup>2+</sup>. At 1 mM Co<sup>2+</sup> and allitol concentrations of 50, 150, and 250 mM, the <sc>D</sc>-allulose yields of 97, 56, and 38%, respectively, were obtained after reaction for 4 h under optimal conditions, which were much higher than that obtained by using the epimerase method of about 30%.</p>