ENDOGENOUS RESPIRATION OF BACILLUS CEREUS

Clifton, C. E. (Stanford University, Stanford, Calif.), and J. M. Sobek. Endogenous respiration of Bacillus cereus . J. Bacteriol. 82: 252–256. 1961.—The endogenous respiration of washed cells of Bacillus cereus varies with the nature of the growth medium and with time. The respiratory quotient of cells harvested from nutrient agar remained quite constant around 1.00 over a 2-hr period of respiration, whereas that of cells grown on glucose-nutrient agar decreased from 0.97 for the first hour to 0.87 for the second hour. Considerable amounts of ammonia were formed, the number of moles per mole of oxygen consumed decreasing with time for agar-grown cells and increasing for glucose-grown ones. C 14 -labeled, agar-grown cells utilized materials insoluble in cold or hot 5% trichloroacetic acid, ethanol, or chloroform as their endogenous substrate, the same behavior being noted with glucose-grown cells except that they utilized both hot trichloroacetic-soluble and -insoluble materials. These results indicate that the bulk of the endogenous substrates are chemically complex and, at least in part, are nitrogenous in character.