Changes

==Roles in the Body==

==Roles in the Body==

#'''Carbon Transfer''': Cobalamin is a cofactor for methionine synthase, used to transfer a methyl group to homocysteine and regenerate methionine and tetrahydrofolate.<ref name="NRC"/><ref name="Shane">Shane B. Folic Acid, Vitamin B12, and Vitamin B6. In Biochemical and physiological aspects of human nutrition. 2000 Philadelphia, PA: WB Saunders Company p. 500-511.</ref>.

#'''Carbon Transfer''': Cobalamin is a cofactor for methionine synthase, used to transfer a methyl group to homocysteine and regenerate methionine and tetrahydrofolate.<ref name="NRC"/><ref name="Shane">Shane B. Folic Acid, Vitamin B12, and Vitamin B6. In Biochemical and physiological aspects of human nutrition. 2000 Philadelphia, PA: WB Saunders Company p. 500-511.</ref>.

#'''Propionate Metabolism''': Propionyl-CoA is created during catabolism of specific amino acids (i.e., isoleucine, valine, methionine and threonine) as well as mitochondrial β-oxidation of odd-chain fatty acids.4 Propionyl-CoA is then converted to methylmalonyl-CoA via the biotin-containing enzyme proprionyl-CoA carboxylase.  The cobalamin-dependant enzyme, methylmalonyl-CoA mutase, then converts methylmalonyl-CoA to succinyl-CoA, which can feed into the tricarboxylic acid (TCA) cycle, be used for heme synthesis, or as a carbon skeleton for gluconeogenesis.

#'''Propionate Metabolism''': Propionyl-CoA is created during catabolism of specific amino acids (i.e., isoleucine, valine, methionine and threonine) as well as mitochondrial β-oxidation of odd-chain fatty acids<ref name="Shane"/>. Propionyl-CoA is then converted to methylmalonyl-CoA via the biotin-containing enzyme proprionyl-CoA carboxylase.  The cobalamin-dependant enzyme, methylmalonyl-CoA mutase, then converts methylmalonyl-CoA to succinyl-CoA, which can feed into the tricarboxylic acid (TCA) cycle, be used for heme synthesis, or as a carbon skeleton for gluconeogenesis.

==Consequences of Cobalamin Deficiency==

==Consequences of Cobalamin Deficiency==