| Title | Mechanism of Thermoanaerobacterium saccharolyticum ss-xylosidase: Kinetic studies |
| Publication Type | Journal Article |
| Year of Publication | 2002 |
| Authors | Vocadlo, DJ, Wicki, J, RUPITZ, K, Withers, SG |
| Journal | BIOCHEMISTRY |
| Volume | 41 |
| Pagination | 9727-9735 |
| Date Published | AUG 6 |
| ISSN | 0006-2960 |
| Abstract | {The catalytic mechanism of Thermoanaerobacterium saccharolyticum beta-xylosidase (XynB) from family 39 of glycoside hydrolases has been subjected to a detailed kinetic investigation using a range of substrates. The enzyme exhibits a bell-shaped pH dependence of k(cat)/K(m), reflecting apparent pK(a) values of 4.1 and 6.8. The k(cat) and k(cat)/K(m) values for a series of aryl xylosides have been measured and used to construct two Bronsted plots. The plot of log(k(cat)/K(m)) against the pK(a) of the leaving group reveals a significant correlation (beta(1g) = -0.97, r(2) = 0.94 |
| DOI | 10.1021/bi020077v |
