Lawrence, N. L. (University of Alabama, Birmingham) and Yun-Chuan Tsan. Reaction of spores and cells of Bacillus cereus with pyrimidine ribosides. J. Bacteriol. 83:228-233. 1962.-Cytidine deaminase and uridine ribosidase were essentially inactive in heat-resistant spores of Bacillus cereus T, but the activity increased as the spores germinated and proceeded to the vegetative form. The activity of germinated spores on cytidine was evident only after several hours lag, but then was nearly equal to that of vegetative cells. Cytosine deaminase was absent from all these preparations, but deoxycytidine was deaminated at nearly the same rate as cytidine. In the absence of added phosphate, cytidine was converted to uracil by intact vegetative cells more completely than was uridine.