Biochemistry 4th Edition by Christopher Mathews,Kensal van Holde, Dean Appling, Spencer Anthony Cahill

تمرين 2

The following diagram shows the biosynthesis of B 12 coenzymes, starting with the vitamin. DMB is dimethylbenzimidazole.
(a) What one additional substrate or cofactor is required by enzyme B
(b) Genetic deficiency in animals of enzyme C would result in excessive urinary excretion of what compound
(c) Some forms of the condition described in (b) can be successfully treated by injection of rather massive doses of vitamin B l2. What kind of genetic alteration in the enzyme would be consistent with this result
(d) Genetic deficiency in animals of enzyme B will result in excessive urinary excretion of what amino acid