1976 Volume 23 Issue 2 Pages 63-70
1. A homogeneous preparation of pig kidney diamine oxidase was obtained by polyacrylamide gel electrophoresis and immunodiffusion. Its molecular weight was estimated as 170,000 by Sephadex G-200 column chromatography and as 220,000 by SDS-polyacrylamide gel electrophoresis. After mercaptoethanol cleavage of disulfide bonding, the molecular weight of the subunit was 130,000. 2. Little contamination was observed in the preparation of human placenta by SDSpolyacrylamide gel electrophoresis and immunoelectrophoresis and the molecular weight was calculated as 300,000 and 280,000 by the extrapolation from the calibration curve of Sephadex G-200 column chromatography and SDS-polyacrylamide gel electrophoresis, respectively. The subunit was 170,000. 3. By immunodiffusion, immunoelectrophoresis and inhibition test of the enzyme activity using a heterologous antiserum, a good cross-reactivity was observed between the anti-human diamine oxidase serum and pig diamine oxidase. 4. The activities of the two enzymes were not almost inhibited by homologous and heterologous antisera.