Purification and properties of a mitochondrial NAD+ glycohydrolase.
A 60- to 70-fold purification of an NAD+ glycohydrolase from the inner membrane of rat liver mitochondria to apparent homogeneity on sodium dodecyl sulfate (SDS)-polyacrylamide slab gel is described. The minimum molecular weight of the enzyme on polyacrylamide gels in the presence of SDS is around 62,000. The enzyme splits NAD+ to ADP-ribose and, presumably, nicotinamide. No phosphatase or phosphodiesterase activity is detected in the purified enzyme preparation. The enzyme shows high activity with NAD+ and moderate activity with NADP+ as substrates NAD(P)Hs are poor substrates. ATP and nicotinamide inhibit the enzyme. A possible participation of the enzyme in the mechanism of calcium release from rat liver mitochondria is discussed.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D008930:Mitochondria, Liver / Q000201:enzymology*; D009699:N-Glycosyl Hydrolases / Q000302:isolation & purification*; D009244:NAD+ Nucleosidase; D051381:Rats; D012967:Sodium Dodecyl Sulfate; D013379:Substrate Specificity
D012967:Sodium Dodecyl Sulfate; D009699:N-Glycosyl Hydrolases; D009244:NAD+ Nucleosidase