METABOLISM OF w-AMINO ACIDS I. FERMENTATION OF zy-AMINOBUTYRIC ACID BY Clostridium aminobutyricum NT. Sp.1

A number of amino acids are known to undergo reductive deamination reactions; in the general case, the products are the corresponding fatty acid and ammonia (Stickland, 1934; Woods, 1936). In at least one instance, that of the reduction of glycine to acetate and ammonia by Clostridium sticklandii, useful energy in the form of adenosine triphosphate is made available to the organism as a result of catalysis of the over-all reaction (Stadtman and Elliott, 1956). Related anaerobic bacteria such as Clostridium sporogenes and Clostridium lentoputrescens appear to share this ability (Stadtman, 1959). In view of the fact that the mechanism of this reduction is as yet unknown, it was (leemed de-sirable to search for microorganisms able to ferment related amino acids. Such organisms might provide more suitable biological systems for the elucidation of the mechanism of reductive deaminations. The substrates chosen were two higher hom-ologues of glycine, namely,-y-aminobutyrate and A-aminovalerate. Two different species of anaerobic bacteria were isolated by the enrich-ment culture technique,3 specific for each one of these amino acids respectively, when furnished as the sole carbon and nitrogen source. The present paper describes the isolation and identi-fication of the organism that grows on y-amino-butyrate together with the stoichiometry of the fermentation that it catalyzes. Similar studies 1 A culture of this organism has been suibmitte