Semicarbazide-sensitive amine oxidase in pig heart.

A semicarbazide-sensitive amine oxidase (SSAO) (E.C.1.4.3.6) has been purified from pig heart. Western blot analysis showed that the enzyme reacts with a polyclonal antibody raised against homogeneous crystalline pig plasma benzylamine oxidase (BAO). A subunit molecular mass of 97 KDa obtained by SDS electrophoresis is identical to the plasma enzyme. The purification procedure consisted of sequential DEAE cellulose, octyl-Sepharose, Con A-Sepharose and hydroxyapatite columns. Two peaks of activity were obtained on octyl-Sepharose which were found to be kinetically and immunologically indistinguishable. The specific activity of the purified enzyme was 0.045 mumol/min/mg of protein at 37 degrees C and the Km for benzylamine was estimated to be 63 microM. The enzyme was inhibited by carbonyl reagents such as semicarbazide but was insensitive to the effect of pargyline.