Studies on sucrose synthetase. Kinetic mechanism |
| |
Authors: | R A Wolosiuk H G Pontis |
| |
Affiliation: | Departamento de Biología, Fundación Bariloche, C. C. 138, San Carlos de Bariloche, Argentina |
| |
Abstract: | The kinetic properties of Helianthus tuberosus sucrose synthetase, which catalyzes the reaction UDP-glucose + fructose = UDP + sucrose, have been studied. A plot of the reciprocal initial velocity versus reciprocal substrate concentration gave a series of intersecting lines indicating a sequential mechanism. Product inhibition studies showed that UDP-glucose was competitive with UDP, whereas fructose was competitive with sucrose and uncompetitive with UDP. On the other hand, a dead-end inhibitor, salicine, was competitive with sucrose and uncompetitive with UDP. The results of initial velocity, product, and dead-end inhibition studies suggested that the addition of substrates to the enzyme follows an ordered mechanism. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|