Identification and characteristics of a novel mitochondrial 5'-nucleotidase in rat liver.
In rat liver mitochondria there exists an AMP-dephosphorylating activity which converts external 5'-AMP to adenosine. It exhibits a pH optimum of 7.5 and a Km(AMP) of 0.085 mM. Furthermore, this activity is stimulated by magnesium (Km = 0.5 mM) and seems to be not affected by low concentrations of ATP or ADP. From the characteristics of the enzyme the existence of a 5'-nucleotidase in rat liver mitochondria which is localized on the outer surface of the inner mitochondrial membrane was concluded. The enzyme may be important for the production of cellular adenosine.
Henke
W
W
Abteilung für experimentelle Organtransplantation, Leninallee, Berlin, DDR.
Lang
M
M
Dubiel
W
W
Holzhütter
H G
HG
Gerber
G
G
D015720:5'-Nucleotidase; D000249:Adenosine Monophosphate / Q000378:metabolism; D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007425:Intracellular Membranes / Q000201:enzymology; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D008930:Mitochondria, Liver / Q000201:enzymology*; D009708:Nucleotidases / Q000302:isolation & purification* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D000249:Adenosine Monophosphate; D009708:Nucleotidases; D015720:5'-Nucleotidase; D008274:Magnesium