Evidence for four deoxynucleoside kinase activities in extracts of Lactobacillus leichmannii.

Extracts of Lactobacillus leichmannii (ATCC 7830) catalyze the phosphorylation of the four principal deoxynucleosides. Thymidine, deoxyguanosine, and deoxycytidine kinase activities were found to be optimal with deoxyadenosine triphosphate as the phosphoryl donor, whereas deoxycytidine triphosphate was the optimal donor for deoxyadenosine kinase activity. L. leichmannii catalyzes the conversion of deoxycytidine to deoxyuridylic acid, probably by a pathway involving deoxycytidylate deaminase.