Integrated allosteric regulation in the S. cerevisiae carbamylphosphate synthetase - aspartate transcarbamylase multifunctional protein.

ABSTRACT:

Background

The S. cerevisiae carbamylphosphate synthetase - aspartate transcarbamylase multifunctional protein catalyses the first two reactions of the pyrimidine pathway. In this organism, these two reactions are feedback inhibited by the end product UTP. In the present work, the mechanisms of these integrated inhibitions were studied.

Results

The results obtained show that the inhibition is competitive in the case of carbamylphosphate synthetase and non-competitive in the case of aspartate transcarbamylase. They also identify the substrate whose binding is altered by this nucleotide and the step of the carbamylphosphate synthetase reaction which is inhibited. Furthermore, the structure of the domains catalyzing these two reactions were modelled in order to localize the mut

SUBMITTER: Serre V 

PROVIDER: S-EPMC434488 | biostudies-literature | 2004 May

REPOSITORIES: biostudies-literature