[Formation of thymine nucleotides in bone marrow of animals of different species]

The activity of enzymes of thymidine and thymidylic acid phosphorylation up to thymidine triphosphate and dCMP-desaminase was studied in bone marrow of rats, rabbits and dogs. A soluble fraction of hyaloplasm obtained after bone marrow homogenates centrifugation at 105000xg for an hour at 0-4 degrees C used as a source of the enzymes. It is found that the rate of thymidine and TMP phosphorylation up to TTP by the rat and dog bone marrow extracts is approximately the same, in rabbits this process is slower. The formation of TTP from TMP in animals of all three species is 1.4-2 times as active as in thymidine phosphorylation. The highest activity of dCMP-desaminase is found in the bone marrow cells of dogs, in rabbits and rats it is 1.6 and 2 times as low, respectively.