Biosynthesis of porphyrins and related macrocycles. Part 42. Pulse labelling experiments concerning the timing of cobalt insertion during vitamin B12 biosynthesis
Abstract
Pulse labelling experiments using 60Co2+ and [methyl-13C, 14C]-S-adenosyl-L-methionine have established that in the anaerobic organism Propionibacterium shermanii cobalt is inserted into the macrocycle after the second and before the fourth C-methylation step.