title: Rabbit liver dCMP phosphohydrolase: a pyrimidine 5'-nucleotidase I-like enzyme in non-erythrocytic cells.
abstract: A nucleotide phosphomonoesterase activity that preferably hydrolyzed dCMP was detected in rabbit liver and purified approximately 20-fold. The enzyme was similar in the catalytic and molecular properties to pyrimidine 5'-nucleotidase subclass I (P5N-I), which distributed specifically in vertebrate erythrocytes. In addition to liver, the activity was found in rabbit kidney, spleen, heart, intestine, but was not detected in any rat or chicken tissues tested. The rabbit enzyme protein reacted with antibodies against chicken P5N-I. Its pI was estimated to be approximately 5.3, and the enzyme was concluded to consist of single polypeptide of an approximately 38 kDa based on gel filtration and Western blot analysis. The partially purified enzyme preferentially hydrolyzes dCMP, UMP and CMP, K(m) values for these substrates are approximately 0.3 mM, the optimal pH is approximately 7, and the enzyme requires Mg(2+). This nucleotidase may contribute to the regulation of intracellular pyrimidine nucleotides in the rabbit.
authors.affiliation: Department of Biochemistry, Saitama Medical School, 38 Morohongo, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan. shhokar@saitama-med.ac.jp
authors.forename: Shigeru
authors.initials: S
authors.lastname: Hokari
authors.forename: Takashi
authors.initials: T
authors.lastname: Miyazaki
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Kawai
authors.forename: Iwao
authors.initials: I
authors.lastname: Koyama
authors.forename: Tsugikazu
authors.initials: T
authors.lastname: Komoda
mesh_terms: D015720:5'-Nucleotidase / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D002384:Catalysis; D003562:Cytidine / Q000378:metabolism; D004912:Erythrocytes / Q000201:enzymology; D020869:Gene Expression Profiling; D006868:Hydrolysis; D008099:Liver / Q000201:enzymology*; D008110:Liver Extracts; D010744:Phosphoric Monoester Hydrolases / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D013379:Substrate Specificity
chemical_list: D008110:Liver Extracts; D003562:Cytidine; D010744:Phosphoric Monoester Hydrolases; D015720:5'-Nucleotidase