Adenosine deaminase: physical and chemical properties of partially purified mitochondrial and cytosol enzyme from rat liver.
Adenosine deaminase (ADA) was partially purified 486- and 994-fold from rat liver mitochondria and cytosol, respectively. Relative molecular mass of the enzymes from both fractions was 34,000. Km for adenosine and 2'-deoxy-adenosine were 3.08 x 10(-5) M and 3.03 x 10(-5) M for mitochondrial ADA and 3.12 x 10(-5) M and 2.87 x 10(-5) M for cytosolic ADA. The enzyme from both subcellular fractions had the maximum activity at pH 7.5-8.0, and pI 5.2 and 4.2 for mitochondrial and cytosolic enzyme, respectively. The enzyme was inhibited by erythro-9-(2-hydroxy-3-nonyl)adenine and 2'-deoxycoformycin with Ki 4.4 x 10(-7) M and 3.2 x 10(-7) M for mitochondrial ADA and 4.9 x 10(-7) M 2.8 x 10(-7) M for cytosolic ADA. Among the natural nucleoside and deoxynucleotide derivatives tested, deoxy-GTP and UTP inhibited only cytosolic adenosine deaminase by 60% and 40%, respectively.
Fabianowska-Majewska
K
K
Department of General Chemistry, Medical University of Lódź, Poland.
Greger
J
J
D000243:Adenosine Deaminase / Q000737:chemistry* / Q000302:isolation & purification; D058892:Adenosine Deaminase Inhibitors; D000818:Animals; D003600:Cytosol / Q000201:enzymology*; D003839:Deoxyadenosines / Q000633:toxicity*; D008930:Mitochondria, Liver / Q000201:enzymology*; D009705:Nucleosides / Q000494:pharmacology; D009711:Nucleotides / Q000494:pharmacology; D051381:Rats
D058892:Adenosine Deaminase Inhibitors; D003839:Deoxyadenosines; D009705:Nucleosides; D009711:Nucleotides; D000243:Adenosine Deaminase; C058118:2'-deoxyadenosine