期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：5
页码：1393-1397
DOI：10.1073/pnas.79.5.1393
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Several studies have shown that both terminal oxygen atoms of biliverdin are derived from molecular oxygen. Since the conversion of verdohemochrome to biliverdin has been assumed to be hydrolytic, these findings seemed to exclude verdohemochrome as an intermediate in the degradation of heme to biliverdin. Coupled oxidation of myoglobin and ascorbate yielded a pure preparation of verdohemochrome IX alpha. The structure and ferrous state of this product were determined from its composition, ligand reactions, 1H NMR spectrum, and conversion to biliverdin IX alpha dimethyl ester. Reaction with ascorbate and 18O2 converted this compound to biliverdin that contained an atom of 18O. Successive treatment of verdohemochrome, first oxidation with H2O2 and then reduction with phenylhydrazine, yielded the iron complex of biliverdin. These results showed that hydrolysis is not an obligatory step in the conversion of verdohemochrome to biliverdin and, moreover, indicated how heme can be converted, with verdohemochrome as an intermediate, into biliverdin in which the two terminal oxygen atoms are derived from different O2 molecules.
