Large cell stage in the genus Bacillus.

Johnson, Roy M. (Arizona State University, Tempe). Large cell stage in the genus Bacillus. J. Bacteriol. 82:418-424. 1961.-Synchronous cultures of Bacillus polymyxa and Bacillus cereus produced a transitory large cell stage with increased nuclear material concomitant with a drop in viable count during growth in a defined medium. A variant of B. cereus that required no organic nitrogen for growth and sporulation was inhibited by serine and this inhibition reversed by equimolar amounts of threonine. Serine inhibition occurred before the large cell stage but not after. The significance of this large cell stage as regards transformation studies, nucleic acid analysis, and sporulation was considered.