COMPARISON OF THE MECHANISM OF GLYCEROL OXIDATION IN AEROBICALLY AND ANAEROBICALLY GROWN STREPTOCOCCUS FAECALIS

Abstract

S. faecalis grown aerobically on glucose contains a phosphorylated system for the oxidation of glycerol, including a glycerol kinase and a flavin adenine dinucleotide-linked [alpha]-glycero-phosphate oxidase. This enzyme does not reduce diphosphopyridine nucleotide (DPN). Anaerobically grown cells, deficient in this phosphorylated pathway, possess a DPN-linked glycerol dehydrogenase which is coupled with flavin-linked dihydrodephosphopyridine oxidizing enzyme systems. The glycerol dehydrogenase appears to be lacking in aerobically grown cells. Extracts of anaerobically grown cells reduce fumaric acid with either dihydro-DPN or reduced free flavins. The reduction of free flavins by dihydro-DPN was observed in extracts of cells grown both aerobically and anaerobically.