Roessner C A, Warren M J, Santander P J, Atshaves B P, Ozaki S, Stolowich N J, Iida K, Scott A I
Department of Chemistry, Texas A&M University, College Station 77843-3255.
FEBS Lett. 1992 Apr 13;301(1):73-8. doi: 10.1016/0014-5793(92)80213-z.
Nine of the cbi genes from the 17.5 kb cob operon of Salmonella typhimurium previously shown by genetic studies to be involved in the biosynthesis of cobinamide from precorrin-2, have been subcloned and expressed in Escherichia coli. Seven of the gene products were found in the soluble fraction of cell lysates and have been purified. The gene products corresponding to cbi E, F, H and L were shown by SAM binding and by homology with other SAM-binding proteins to be candidates for the methyltransferases of vitamin B12 biosynthesis. The enzymatic functions of the gene products of cbiL and cbiF are associated with C-methylation at C-20 of precorrin-2 and C-11 of precorrin-3.
