Biosynthesis of type-III porphyrins: proof of intact ezymic conversion of the head-to-tail bilane into uro'gen-III by intramolecular rearrangement
Abstract
Synthesis of doubly 13C-labelled forms of the unrearranged bilane (2) allows proof beyond doubt that the biosynthesis of natural porphyrins (and relatives) occurs by head-to-tail assembly of 4 PBG units followed by intramolecular rearrangement.