Derivatives of vitamin B 12 (cobalamin) are essential cofactors for enzymes required in
intermediary metabolism. Defects in cobalamin metabolism lead to disorders characterized …

The cobalamin F (cblF) defect is caused by disturbed lysosomal release of cobalamin
(vitamin B12) into the cytoplasm caused by mutations in the LMBRD1 gene. We present the …

Cobalamin (Cbl), or vitamin B 12, is required for activity of the mitochondrial enzyme,
methylmalonyl-CoA mutase, and the cytoplasmic enzyme, methionine synthase. A number …

Three distinct classes of human mutations (cbl A, cbl B, and cbl C) cause defective synthesis
of cobalamin (Cbl; vitamin B12) coenzymes. Cultured fibroblasts from that unique class (cbl …

Cobalamin G (cblG) and cobalamin J (cblJ) defects are rare disorders of cbl metabolism
caused by MTR and ABCD4 mutations, respectively. Patients with atypical biochemical …

Methylmalonic aciduria, cblB type (OMIM 251110) is an inborn error of vitamin B12
metabolism that occurs due to mutations in the MMAB gene. MMAB encodes the enzyme …

AN increasing variety of hereditary disorders of intracellular cobalamin metabolism, usually
first detected because of the presence of methylmalonic aciduria (cblA, cblB, and cblF …

In humans vitamin B 12 (cobalamin, Cbl) must be converted into two coenzyme forms,
methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl), in order to maintain …

Inherited disorders of vitamin B 12 include those which involve the inability of the vitamin to
be absorbed from the gut and transported to the appropriate tissues, and those in which the …

Deficient activity of an enzyme can result from a defect in the conversion of the vitamin to a
co-enzyme as well from an abnormal apo-enzyme or disturbed binding of co-enzyme to …