S. Balachandran, R. A. Vishwakarma, S. M. Monaghan, A. Prelle, N. P. J. Stamford, F. J. Leeper and A. R. Battersby
"Biosynthesis of Porphyrins and Related Macrocycles, Part 42. Pulse Labelling Experiments Concerning the Timing of Cobalt Insertion During Vitamin B12 Biosynthesis"
J. Chem. Soc., Perkin Trans. 1,1994, 487-491. Full Text
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.
Department of Chemistry
University of Cambridge