A variety of cobalamin analogues synthesized chemically or microbiologically were used to study the corrinoid specificities of cell growth and the cobalamin uptake system in z. Although could not utilize most of the analogues for cell growth, benzimidazolyl cobamide, cyanocobalamin- -phosphate, and cyanocobalamin--, -- and --monocarboxylates had effects similar to that of cyanocobalamin on cell growth. It is suggested that cells have the ability to synthesize ‘complete cobalamin’ from the acid derivatives (amidation reaction) and/or the phosphate derivative (dephosphorylation reaction). Inhibition of uptake of radiolabelled cyanocobalamin caused by addition of various analogues indicates that both the α-lower axial ligand (the cobalt-coordinated nucleotide) and the ()-propionamide side-chain of the cobalamin molecule are essential for the cobalamin uptake system in . These results indicate that there are different corrinoid specificities for cell growth and the cobalamin uptake system in z.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error