Reaction: D-psicose = D-fructose
Glossary: D-psicose = D-ribo-hex-2-ulose = D-allulose
Other name(s): DPEase (ambiguous)
Systematic name: D-psicose 3-epimerase
Comments: The enzyme is highly specific for D-psicose and shows very low activity with D-tagatose (cf. EC 5.1.3.31, D-tagatose 3-epimerase). The enzyme from the bacterium Clostridium scindens requires Mn2+ [1], whereas the enzymes from the bacteria Clostridium cellulolyticum [2,5], Clostridium sp. BNL1100 [3], and Clostridium bolteae [4] require Co2+ as optimum cofactor. The enzyme from Ruminococcus sp. [6] is not dependent on the presence of metal ions, but its activity is enhanced by Mn2+.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Mu, W., Chu, F., Xing, Q., Yu, S., Zhou, L. and Jiang, B. Cloning, expression, and characterization of a D-psicose 3-epimerase from Clostridium cellulolyticum H10. J. Agric. Food Chem. 59 (2011) 7785-7792. [PMID: 21663329]
2. Chan, H.C., Zhu, Y., Hu, Y., Ko, T.P., Huang, C.H., Ren, F., Chen, C.C., Ma, Y., Guo, R.T. and Sun, Y. Crystal structures of D-psicose 3-epimerase from Clostridium cellulolyticum H10 and its complex with ketohexose sugars. Protein Cell 3 (2012) 123-131. [PMID: 22426981]
3. Zhu, Y., Men, Y., Bai, W., Li, X., Zhang, L., Sun, Y. and Ma, Y. Overexpression of D-psicose 3-epimerase from Ruminococcus sp. in Escherichia coli and its potential application in D-psicose production. Biotechnol. Lett. 34 (2012) 1901-1906. [PMID: 22760176]
4. Zhang, W., Fang, D., Xing, Q., Zhou, L., Jiang, B. and Mu, W. Characterization of a novel metal-dependent D-psicose 3-epimerase from Clostridium scindens 35704. PLoS One 8 (2013) e62987. [PMID: 23646168]
5. Mu, W., Zhang, W., Fang, D., Zhou, L., Jiang, B. and Zhang, T. Characterization of a D-psicose-producing enzyme, D-psicose 3-epimerase, from Clostridium sp. Biotechnol. Lett. 35 (2013) 1481-1486. [PMID: 23660703]
6. Jia, M., Mu, W., Chu, F., Zhang, X., Jiang, B., Zhou, L.L. and Zhang, T. A D-psicose 3-epimerase with neutral pH optimum from Clostridium bolteae for D-psicose production: cloning, expression, purification, and characterization. Appl. Microbiol. Biotechnol. 98 (2014) 717-725. [PMID: 23644747]