Premium
The identification of the acid–base catalyst of α‐arabinofuranosidase from Geobacillus stearothermophilus T‐6, a family 51 glycoside hydrolase
Author(s) -
Shallom Dalia,
Belakhov Valery,
Solomon Dmitry,
Gilead-Gropper Sara,
Baasov Timor,
Shoham Gil,
Shoham Yuval
Publication year - 2002
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(02)02343-8
Subject(s) - geobacillus stearothermophilus , glycoside hydrolase , chemistry , biochemistry , hydrolase , glycoside , catalysis , stereochemistry , enzyme , thermophile
The α‐ L ‐arabinofuranosidase from Geobacillus stearothermophilus T‐6 (AbfA T‐6) belongs to the retaining family 51 glycoside hydrolases. The conserved Glu175 was proposed to be the acid–base catalytic residue. AbfA T‐6 exhibits residual activity towards aryl β‐ D ‐xylopyranosides. This phenomenon was used to examine the catalytic properties of the putative acid–base mutant E175A. Data from kinetic experiments, pH profiles, azide rescue, and the identification of the xylopyranosyl azide product provide firm support to the assignment of Glu175 as the acid–base catalyst of AbfA T‐6.