Selenium-dependent growth and glycine fermentation by Clostridium purinolyticum

Clostridium purinolyticum fermented glycine as a sole carbon and energy source according to the equation: 4 Glycine + 2H2O leads to 3 Acetate + 2CO2 + 4NH3. The organism required adenine as a supplement and selenium compounds as micronutrients for growth. The molar growth yield on glycine was 6.5 g dry wt. Radiochemical and enzymic investigations revealed a new fermentation pathway for glycine in which 1 mol glycine was completely oxidized to CO2 and the generated reducing equivalents were used to reduce a further 3 mol glycine to acetate via the glycine reductase system. This reaction was associated with the formation of ATP.