BACKGROUND: Since 1975 cells lines from patients with suspected inborn errors of vitamin
B12 metabolism have been referred to our laboratory because of elevations of …

Inborn errors of vitamin B12 (cobalamin) metabolism are associated with homocystinuria
and methylmalonic aciduria, either alone or in combination. A number of these disorders …

Background Vitamin B12 (cobalamin) is an essential cofactor in several metabolic pathways.
Intracellular conversion of cobalamin to its two coenzymes, adenosylcobalamin in …

Inborn errors of vitamin B12 (cobalamin) metabolism are characterized by decreased
production of active cobalamin cofactors and subsequent deficiencies in the activities of …

All of vitamin B12 in nature is of microbial origin. Cobalamin, as vitamin B12 should correctly
be termed, is a large polar molecule that must be bound to specialized transport proteins to …

An infant with vitamin B12-responsive methylmalonic aciduria and no homocystinuria or
megaloblastic anemia presented with stomatitis, glossitis, convulsions, and developmental …

Cobalamin (vitamin B 12) is required for activity of the enzymes methylmalonyl-CoA mutase
and methionine synthase in human cells. Inborn errors affecting cobalamin uptake or …

We describe an inborn error of vitamin B12 metabolism in an infant who had severe
developmental delay, megaloblastic anemia, and homocystinuria. There was no evidence of …

Vitamin B 12 (Cbl) is needed for just two metabolic reactions in man, the methylation of
homocysteine to methionine (cofactor methyl-Cbl) and the conversion of methylmalonyl-CoA …

Inborn errors of vitamin B12 (cobalamin, Cbl) metabolism are autosomal recessive disorders
and have been classified into nine distinct complementation classes (cblA-cblH and mut) …