Pyruvate oxidase activity dependent on thiamine pyrophosphate, flavin adenine dinucleotide and orthophosphate inStreptococcus sanguis

Oxygen uptake by Streptococcus sanguis ATCC10556 in the presence of pyruvate was studied. In permeabilized cells pyruvate oxidase activity dependent on thiamine pyrophosphate (TPP), flavin adenine dinucleotide (FAD) and orthophosphate was demonstrated. The activity was ten times higher in cells grown aerobically than in cells grown anaerobically. Acetyl phosphate was a product, and 1.1 mol of acetyl phosphate was formed per mol of oxygen taken up. No pyruvate dehydrogenase activity dependent on NAD, coenzyme A (CoA) and TPP was detected.