Lo Leggio Leila, Simmons Thomas J, Poulsen Jens-Christian N, Frandsen Kristian E H, Hemsworth Glyn R, Stringer Mary A, von Freiesleben Pernille, Tovborg Morten, Johansen Katja S, De Maria Leonardo, Harris Paul V, Soong Chee-Leong, Dupree Paul, Tryfona Theodora, Lenfant Nicolas, Henrissat Bernard, Davies Gideon J, Walton Paul H
Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark.
Department of Biochemistry, University Of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK.
Nat Commun. 2015 Jan 22;6:5961. doi: 10.1038/ncomms6961.
Lytic polysaccharide monooxygenases (LPMOs) are recently discovered enzymes that oxidatively deconstruct polysaccharides. LPMOs are fundamental in the effective utilization of these substrates by bacteria and fungi; moreover, the enzymes have significant industrial importance. We report here the activity, spectroscopy and three-dimensional structure of a starch-active LPMO, a representative of the new CAZy AA13 family. We demonstrate that these enzymes generate aldonic acid-terminated malto-oligosaccharides from retrograded starch and boost significantly the conversion of this recalcitrant substrate to maltose by β-amylase. The detailed structure of the enzyme's active site yields insights into the mechanism of action of this important class of enzymes.
裂解多糖单加氧酶（LPMOs）是最近发现的可氧化解构多糖的酶。LPMOs对于细菌和真菌有效利用这些底物至关重要；此外，这些酶具有重要的工业价值。我们在此报告一种淀粉活性LPMO（新型碳水化合物活性酶家族AA13的代表）的活性、光谱和三维结构。我们证明，这些酶可从老化淀粉生成醛糖酸末端的麦芽寡糖，并显著促进β-淀粉酶将这种难降解底物转化为麦芽糖。该酶活性位点的详细结构为这类重要酶的作用机制提供了深入见解。
