HEME SYNTHESIS IN THE SOLUBLE PREPARATION FROM AVIAN ERYTHROCYTES

Abstract

1. An active preparation to synthesize heme from protoporphyrin and iron was solubilized from particulates of avian hemolysate using sodium cholate solution.
2. The preparation has an optimum pH for the activity and is com-pletely inactivated by heat treatment.
3. Protoporphyrin was required as a substrate, though δ-aminolevulinic acid or porphobilinogen could replace it in the present system.
4. The reaction was remarkably accelerated by addition of cysteine or glutathione. The addition of ascorbate in the course of the cholate extraction showed enhancement of the activity of the preparation.
5. Lead, silver, copper, ethylene diamine tetraacetic acid, p-cholomer-curibenzoate and chicken serum considerably inhibited the reaction, while 2, 4-dinitrophenol, malonate and cyanide showed slight or no inhibitory effects.
The authors express their thanks to Prof. H. Yoshikaw a for his constant advice and encouragement during the couse of the work. Thanks are also due to Dr. G. U rata of the institute of Public Health for his valuible discussions and also for the generous gift of porphobilinogen and to Mr. S. Tanaka, Dr. Y. Sugita and Dr. S. Morimoto of this laboratory for their stimulating cliscussions.