Reaction: starch + reduced acceptor + O2 = D-glucono-1,5-lactone-terminated malto-oligosaccharides + short-chain malto-oligosaccharides + acceptor + H2O
Other name(s): LPMO (ambiguous)
Systematic name: starch, hydrogen-donor:oxygen oxidoreductase (D-glucosyl C1-hydroxylating)
Comments: The enzyme cleaves starch in an oxidative manner. It releases fragments of starch with a D-glucono-1,5-lactone at the reducing end. The initially formed α-D-glucono-1,5-lactone at the reducing end of the shortend amylose chain quickly hydrolyses spontaneously to the aldonic acid. In vitro ascorbate has been found to be able to serve as reducing agent. The enzyme contains copper at the active site.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Vu, V.V., Beeson, W.T., Span, E.A., Farquhar, E.R. and Marletta, M.A. A family of starch-active polysaccharide monooxygenases. Proc. Natl. Acad. Sci. USA 111 (2014) 13822-13827. [PMID: 25201969]
2. Gudmundsson, M., Kim, S., Wu, M., Ishida, T., Momeni, M.H., Vaaje-Kolstad, G., Lundberg, D., Royant, A., Stahlberg, J., Eijsink, V.G., Beckham, G.T. and Sandgren, M. Structural and electronic snapshots during the transition from a Cu(II) to Cu(I) metal center of a lytic polysaccharide monooxygenase by X-ray photoreduction. J. Biol. Chem. 289 (2014) 18782-18792. [PMID: 24828494]
3. Lo Leggio, L., Simmons, T.J., Poulsen, J.C., Frandsen, K.E., Hemsworth, G.R., Stringer, M.A., von Freiesleben, P., Tovborg, M., Johansen, K.S., De Maria, L., Harris, P.V., Soong, C.L., Dupree, P., Tryfona, T., Lenfant, N., Henrissat, B., Davies, G.J. and Walton, P.H. Structure and boosting activity of a starch-degrading lytic polysaccharide monooxygenase. Nat. Commun. 6 (2015) 5961. [PMID: 25608804]