STUDIES ON THE NUTRITIONAL REQUIREMENTS OF BRUCELLA

Simplified media were first used for growth of Brucella by ZoBell and Meyer (1930, 1932), but such media produced only slight growth because the accessory growth factor requirements of this group were undetermined. These investiga-tors, however, demonstrated utilization of the ammonium ion as a source of nitrogen and of various organic acids as sources of carbon and energy, and found that cystine was essential for growth, that iron salts were stimulatory, and that glycerol enhanced growth of Brucella. McNutt and Purwin (1931) obtained blight growth of some strains with xylose or arabinose as the sole carbon source. Glucose utilization was reported by Meyer and ZoBell (1932). Kerby (1939) showed that growth of Brucella abortus on Difco "tryptose " agar was enhanced by the addition of nicotinic acid and thiamine. Koser, Breslove, and Dorfman (1941) first obtained abundant growth of Brucella in a chemically defined medium consisting of 17 amino acids, glucose, inorganic salts, thiamine, nicotinamide, biotin, and pantothenic acid. All the strains studied, including Brucella melitensis, B. abortus, and B. suis, require