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822 a.a.
Key reference
DOI no: 10.1042/BJ20060274 Biochem J 398:37-43 (2006) PubMed id: 16646954
Structural dissection of the reaction mechanism of cellobiose phosphorylase. M.Hidaka, M.Kitaoka, K.Hayashi, T.Wakagi, H.Shoun, S.Fushinobu. ABSTRACT
Cellobiose phosphorylase, a member of the glycoside hydrolase family 94, catalyses the reversible phosphorolysis of cellobiose into alpha-D-glucose 1-phosphate and D-glucose with inversion of the anomeric configuration. The substrate specificity and reaction mechanism of cellobiose phosphorylase from Cellvibrio gilvus have been investigated in detail. We have determined the crystal structure of the glucose-sulphate and glucose-phosphate complexes of this enzyme at a maximal resolution of 2.0 A (1 A=0.1 nm). The phosphate ion is strongly held through several hydrogen bonds, and the configuration appears to be suitable for direct nucleophilic attack to an anomeric centre. Structural features around the sugar-donor and sugar-acceptor sites were consistent with the results of extensive kinetic studies. When we compared this structure with that of homologous chitobiose phosphorylase, we identified key residues for substrate discrimination between glucose and N-acetylglucosamine in both the sugar-donor and sugar-acceptor sites. We found that the active site pocket of cellobiose phosphorylase was covered by an additional loop, indicating that some conformational change is required upon substrate binding. Information on the three-dimensional structure of cellobiose phosphorylase will facilitate engineering of this enzyme, the application of which to practical oligosaccharide synthesis has already been established.
Literature references that cite this PDB file's key reference
PubMed id Reference
19124470 M.Hidaka, M.Nishimoto, M.Kitaoka, T.Wakagi, H.Shoun, and S.Fushinobu (2009).
The Crystal Structure of Galacto-N-biose/Lacto-N-biose I Phosphorylase: A LARGE DEFORMATION OF A TIM BARREL SCAFFOLD.J Biol Chem, 284, 7273-7283.
PDB codes: 2zus 2zut 2zuu 2zuv 2zuw
19491100 M.Nakajima, M.Nishimoto, and M.Kitaoka (2009).
Characterization of Three {beta}-Galactoside Phosphorylases from Clostridium phytofermentans: DISCOVERY OF D-GALACTOSYL-{beta}1->4-L-RHAMNOSE PHOSPHORYLASE.J Biol Chem, 284, 19220-19227.
19487233 M.R.De Groeve, M.De Baere, L.Hoflack, T.Desmet, E.J.Vandamme, and W.Soetaert (2009).
Creating lactose phosphorylase enzymes by directed evolution of cellobiose phosphorylase.Protein Eng Des Sel, 22, 393-399.
17587697 M.Nishimoto, and M.Kitaoka (2007).
Identification of the putative proton donor residue of lacto-N-biose phosphorylase (EC 2.4.1.211).Biosci Biotechnol Biochem, 71, 1587-1591. The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB codes are shown on the right.
