2BOE

Catalytic domain of endo-1,4-glucanase Cel6A mutant Y73S from Thermobifida fusca

Summary for 2BOE

• Entry DOI: 10.2210/pdb2boe/pdb
• Related: 1TML 2BOD 2BOF 2BOG
• Descriptor: ENDOGLUCANASE E-2 (2 entities in total)
• Functional Keywords: endoglucanase, thermobifida fusca, tim a/b fold, glycoside hydrolase family 6, methyl cellobiosyl-4-thio-beta-cellobioside, carbohydrate metabolism, cellulose degradation, glycosidase, hydrolase, polysaccharide degradation
• Biological source: THERMOMONOSPORA FUSCA
• Total number of polymer chains: 1
• Total formula weight: 30360.69

Authors

Larsson, A.M.,Bergfors, T.,Dultz, E.,Irwin, D.C.,Roos, A.,Driguez, H.,Wilson, D.B.,Jones, T.A. (deposition date: 2005-04-10, release date: 2005-10-05, Last modification date: 2024-10-16)

Primary citation

Larsson, A.M.,Bergfors, T.,Dultz, E.,Irwin, D.C.,Roos, A.,Driguez, H.,Wilson, D.B.,Jones, T.A.
Crystal Structure of Thermobifida Fusca Endoglucanase Cel6A in Complex with Substrate and Inhibitor: The Role of Tyrosine Y73 in Substrate Ring Distortion.
Biochemistry, 44:12915-, 2005

PubMed Abstract: Endoglucanase Cel6A from Thermobifida fusca hydrolyzes the beta-1,4 linkages in cellulose at accessible points along the polymer. The structure of the catalytic domain of Cel6A from T. fusca in complex with a nonhydrolysable substrate analogue that acts as an inhibitor, methylcellobiosyl-4-thio-beta-cellobioside (Glc(2)-S-Glc(2)), has been determined to 1.5 A resolution. The glycosyl unit in subsite -1 was sterically hindered by Tyr73 and forced into a distorted (2)S(o) conformation. In the enzyme where Tyr73 was mutated to a serine residue, the hindrance was removed and the glycosyl unit in subsite -1 had a relaxed (4)C(1) chair conformation. The relaxed conformation was seen in two complex structures of the mutated enzyme, with cellotetrose (Glc(4)) at 1.64 A and Glc(2)-S-Glc(2) at 1.04 A resolution.

PubMed: 16185060
DOI: 10.1021/BI0506730

Experimental method

X-RAY DIFFRACTION (1.15 Å)