Malate Utilization by a Group D Streptococcus: Regulation of Malic Enzyme Synthesis by an Inducible Malate Permease

Abstract

Induction of an nicotinamide adenine dinucleotide-specific malic enzyme and a malate entry system permits Streptococcus faecalis to grow at the expense of malate. Evidence is presented which shows that biosynthesis of the permease, but not of the malic enzyme, is subject to catabolite repression by glucose. In contrast to the malic enzyme, the catalytic function of the entry system does not appear to be inhibited by intermediate products of glycolysis. Although the induction of the entry system does not appear to be coordinated with the induction of the malic enzyme, the latter process is dependent upon the permease for the transport and accumulation of inducer.