cobalamin metabolic pathway altered metabolic pathway of cofactors, vitamins, nutrients altered cobalamin metabolic pathway 2024-06-05T13:11:50Z A cobalamin (Cbl) metabolic pathway that deviates from what its normal course should be. Cbl deficiency results in hyperhomocysteinemia (due to defects in the conversion of homocysteine to methionine which requires Cbl as a cofactor) and increased levels of methylmalonic acid. Symptoms of Cbl deficiency are bone marrow promegaloblastosis (megaloblastic anemia) due to the inhibition of DNA synthesis (specifically purines and thymidine) and neurological symptoms. Defects in cobalamin (B12) metabolism PW:0002675 gthayman pathway