[Catabolism of threonine in the bacterium Clostridium sticklandii].

Catabolism of L-threonine in the anaerobic bacteria Cl. sticklandii has been studied. Degradation of this amino acid was shown to occur with participation of the following enzymes: NAD-dependent L-threonine-3-dehydrogenase (EC 1.1.1.103), glycine acetyltransferase (EC 2.3.1.29), phosphotransacetylase (EC 2.3.1.8) and acetate kinase (EC 2.7.2.1). The presence of the first two enzymes in Clostridia has been shown for the first time. A scheme of threonine oxidation down to acetic acid and glycine by Cl. sticklandii was proposed. The oxidation of one threonine molecule is coupled with phosphorylation of one ADP molecule and reduction of one NAD+ molecule.