[Kinetic characteristics of microsomal NAD-glycohydrolase natural and solubilized with a non-ionic surface-active substance].

Microsomal rat spleen NAD-glycohydrolase was solubilized by Nonidet P40. The solubilized enzyme shows Nicotinamide inhibition and pH dependence at the same extent as unsolubilized microsomal one. It differs from the latter in having a higher affinity for NAD and NADP, and in showing two peaks, instead of one, on electrofocusing: the former with a pH 5 pI without any activity, the latter with a pH 4, 1 pI with a high NAD-ase activity.