| Affiliation: | (1) Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701, Korea;(2) Department of Chemical and Biomolecular Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701, Korea;(3) Division of Applied Life Science, EB-NCRC, Gyeongsang National University, Gajwa-dong 900, Jinju, 660-701, Korea |
| Abstract: | The rpiB gene, encoding ribose-5-phosphate isomerase (RpiB) from Clostridium thermocellum, was cloned and expressed in Escherichia coli. RpiB converted d-psicose into d-allose but it did not convert d-xylose, l-rhamnose, d-altrose or d-galactose. The production of d-allose by RpiB was maximal at pH 7.5 and 65°C for 30 min. The half-lives of the enzyme at 50°C and 65°C were 96 h and 4.7 h, respectively. Under stable conditions of pH 7.5 and 50°C, 165 g d-allose l−1 was produced without by-products from 500 g d-psicose l−1 after 6 h. |
