title: Low cytidine deaminase levels in human hematopoietic cell lines.
abstract: Purine and pyrimidine enzyme profiles of human cell lines have been investigated. A novel observation was the finding that most of the cell lines showed very low or undetectable levels of cytidine (deoxycytidine) deaminase, while they possessed pyrimidine 5'-nucleotidase, cytidine and deoxycytidine kinase activities. Most cell lines showed high levels of adenosine deaminase and purine nucleoside phosphorylase activities and low levels of purine 5'-nucleotidase. We propose that high adenosine deaminase and purine nucleoside phosphorylase activities and low cytidine deaminase activity may be of importance for immature hematopoietic cells in order to ensure a balanced synthesis of the DNA precursors.
mesh_terms: D002460:Cell Line; D003564:Cytidine Deaminase / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000201:enzymology*; D006801:Humans; D009700:Nucleoside Deaminases / Q000378:metabolism*; D011687:Purines / Q000378:metabolism; D011743:Pyrimidines / Q000378:metabolism
chemical_list: D011687:Purines; D011743:Pyrimidines; D009700:Nucleoside Deaminases; D003564:Cytidine Deaminase; C030986:pyrimidine