Structure and mechanisms of Escherichia coli aspartate transcarbamoylase.

ABSTRACT: Enzymes catalyze a particular reaction in cells, but only a few control the rate of this reaction and the metabolic pathway that follows. One specific mechanism for such enzymatic control of a metabolic pathway involves molecular feedback, whereby a metabolite further down the pathway acts at a unique site on the control enzyme to alter its activity allosterically. This regulation may be positive or negative (or both), depending upon the particular system. Another method of enzymatic control involves the cooperative binding of the substrate, which allows a large change in enzyme activity to emanate from only a small change in substrate concentration. Allosteric regulation and homotropic cooperativity are often known to involve significant conformational changes in the structure of the prot

SUBMITTER: Lipscomb WN 

PROVIDER: S-EPMC3276696 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature