Characterization and kinetics of phosphopantothenoylcysteine synthetase from Enterococcus faecalis.

ABSTRACT: The enzyme phosphopantothenoylcysteine synthetase (PPCS) catalyzes the nucleotide-dependent formation of phosphopantothenoylcysteine from (R)-phosphopantothenate and L-cysteine in the biosynthetic pathway leading to the formation of the essential biomolecule, coenzyme A. The Enterococcus faecalis gene coaB encodes a novel monofunctional PPCS which has been cloned into pET23a and expressed in Escherichia coli BL21 AI. The heterologous expression system yielded 30 mg of purified PPCS per liter of cell culture. The purified enzyme chromatographed as a homodimer of 28 kDa subunits on Superdex HR 200 gel filtration resin. The monofunctional protein displayed a nucleotide specificity for cytidine 5'-triphosphate (CTP) analogous to that seen for bifunctional PPCS expressed by most prokaryotes. Ki

SUBMITTER: Yao J 

PROVIDER: S-EPMC2892170 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature