Polypyrrole intermediates in porphyrin biosynthesis. Studies with Euglena gracilis

Abstract

1. 1. Evidence for the formation of pyrrolic intermediates resulting from the action of a whole enzyme system and deaminase preparations from Euglena gracilis on porphobilinogen, under normal anaerobic conditions is reported. 2. 2. It was found that the activity of Euglena gracilis pellet was not affected by the presence of air; the yield of porphyrinogens being the same under anaerobiosis and aerobiosis. Both with pellet and deaminase preparations, two phases in porphyrinogen synthesis were observed, a slow and a rapid one, suggesting that some intermediates in the reaction were formed. 3. 3. The nature of these intermediates was investigated by incubating them with different enzyme preparations and PBG. Results obtained suggested that the polypyrroles formed from the whole system and deaminase were different. They did not behave as substrates but as intermediates m the reaction and significantly inhibited total porphyrinogen formation. It is proposed that these intermediates could be in high percentage larger polypyrrylmethanes.