Dobrogosz, Walter J. (Pennsylvania State University, University Park) and Robert W. Stone. Oxidative metabolism in Pediococcus pentosaceus. I. Role of oxygen and catalase. J. Bacteriol. 84:716-723. 1962.-Studies were conducted on the physiological behavior of several strains of Pediococcus pentosaceus isolated from alfalfa silages. Although these organisms are regarded as homofermentative lactic acid bacteria which metabolize carbohydrates via the classic reactions of glycolysis, this investigation showed that they were capable of developing other physiologically important reactions related to carbohydrate metabolism. Growth on glycerol, for example, was shown to depend on the development of aerobic reactions, and was directly related to the catalase content of the various strains tested. These organisms were shown to be devoid of a cytochrome system, thus implicating an active flavoprotein system in oxidative reactions. A study of the end products of aerobic glycerol metabolism suggested that glycerol was oxidized to the pyruvate level, with subsequent reactions involving pyruvate leading to the accumulation of lactate, acetate, acetoin, and CO(2) in a molar ratio of approximately 1:1:1:3.