1gz1
From Proteopedia
MUTANT D416A OF THE CELLOBIOHYDROLASE CEL6A FROM HUMICOLA INSOLENS IN COMPLEX WITH METHYL-CELLOBIOSYL-4-DEOXY-4-THIO-BETA-D-CELLOBIOSIDE
Overview
The enzymatic degradation of cellulose continues to be one of the most important enzyme-catalysed reactions. Glycoside hydrolases from family GH-6 hydrolyse cellulose with inversion of the configuration of the anomeric carbon. Whilst the catalytic proton donor has been clearly identified (Asp226 in Humicola insolens Cel6A), the identification and even the existence of a potential Bronsted base remains unclear. Equally controversial is the role of surface-loop flexibility. Here, the structure of the D416A mutant of the H. insolens cellobiohydrolase Cel6A in complex with a non-hydrolysable thiooligosaccharide methyl cellobiosyl-4-thio-beta-cellobioside at 1.9 A resolution is presented. Substrate distortion in the -1 subsite, to a (2)S(0) skew-boat conformation, is observed, similar to that seen in the analogous Trichoderma reesei Cel6A structure [Zou et al. (1999), Structure, 7, 1035-1045], but the active-centre N-terminal loop of the H. insolens enzyme is found in a more open conformation than described for previous structures.
About this Structure
1GZ1 is a Single protein structure of sequence from Humicola insolens. Full crystallographic information is available from OCA.
Reference
Structure of the Humicola insolens cellobiohydrolase Cel6A D416A mutant in complex with a non-hydrolysable substrate analogue, methyl cellobiosyl-4-thio-beta-cellobioside, at 1.9 A., Varrot A, Frandsen TP, Driguez H, Davies GJ, Acta Crystallogr D Biol Crystallogr. 2002 Dec;58(Pt 12):2201-4. Epub 2002, Nov 23. PMID:12454501 Page seeded by OCA on Fri May 2 18:11:55 2008
