Oxidation of putrescine, spermidine and spermine by diamino-oxidase from mouse liver]

Optimal conditions to determine the activity of diaminooxidase in mouse liver homogenate are described. Maximal oxidation rate for putrescine was found to take place at a concentration of 20 mM and pH 9.5, and for spermidine and spermine--at 10 mM concentration and pH 9.2. The rate of tyramine oxidation was maximal at pH 7.8. Apparent KM values were 4.98-10(-3 M, 1-10(-3) M and 0.8-10(-3) M for putrescine, spermidine and spermine respectively. Hydroxylamine did not inhibit the rate of putrescin oxidation at optimal pH value.