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1up6
From Proteopedia
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STRUCTURE OF THE 6-PHOSPHO-BETA GLUCOSIDASE FROM THERMOTOGA MARITIMA AT 2.55 ANGSTROM RESOLUTION IN THE TETRAGONAL FORM WITH MANGANESE, NAD+ AND GLUCOSE-6-PHOSPHATE
Overview
Among the numerous well-characterized families of glycosidases, family 4 appears to be the anomaly, requiring both catalytic NAD+ and a divalent metal for activity. The unusual cofactor requirement prompted the proposal of a mechanism involving key NAD+-mediated redox steps as well as elimination of the glycosidic oxygen. Primary kinetic isotope effects for the 2- and 3-deutero substrate analogues, isotopic exchange with solvent, and structural analysis of a 6-phospho--glucosidase, BglT (E.C. 3.2.1.6), provided evidence in support of the proposed mechanism, which has striking resemblances to that of the sugar dehydratases. Furthermore, analysis of the stereochemical outcome indicated that family 4 enzymes are retaining glycosidases.
About this Structure
1UP6 is a [Single protein] structure of sequence from [Thermotoga maritima] with G6P, MN, SO4 and NAD as [ligands]. Active as [Endo-1,3(4)-beta-glucanase], with EC number [3.2.1.6]. Structure known Active Site: AC1. Full crystallographic information is available from [OCA].
Reference
An unusual mechanism of glycoside hydrolysis involving redox and elimination steps by a family 4 beta-glycosidase from Thermotoga maritima., Yip VL, Varrot A, Davies GJ, Rajan SS, Yang X, Thompson J, Anderson WF, Withers SG, J Am Chem Soc. 2004 Jul 14;126(27):8354-5. PMID:15237973
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