MMAB transfers adenosyl group from ATP to cob(I)alamin

Stable Identifier
Reaction [transition]
Homo sapiens
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Mitochondrial cob(I)yrinic acid a,c-diamide adenosyltransferase (MMAB) is an enzyme involved in the adenosylation of cobalamin. MMAB transfers an adenosyl group from ATP to cob(I)alamin (B12s) to form adenosylcabalamin (AdoCbl) (Fan & Bobik 2008, Leal et al. 2003). Defects in MMAB cause methylmalonic aciduria type cblB (MMAB aka methylmalonic aciduria type B or vitamin B12-responsive methylmalonicaciduria of cblB complementation type; MIM:251110). Affected individuals have methylmalonic aciduria and metabolic ketoacidosis, despite a functional methylmalonyl-CoA mutase. In severe cases, newborns become severely acidotic and may die if acidosis is not treated promptly (Dobson et al. 2002).

Literature References
PubMed ID Title Journal Year
12514191 Identification of the human and bovine ATP:Cob(I)alamin adenosyltransferase cDNAs based on complementation of a bacterial mutant

Bobik, TA, Kima, PE, Park, SD, Leal, NA

J. Biol. Chem. 2003
12438653 Identification of the gene responsible for the cblA complementation group of vitamin B12-responsive methylmalonic acidemia based on analysis of prokaryotic gene arrangements

Dobson, CM, Hudson, T, Doré, C, Gravel, RA, Rosenblatt, DS, Wu, X, Leclerc, D, Wai, T, Wilson, A

Proc. Natl. Acad. Sci. U.S.A. 2002
18251506 Functional characterization and mutation analysis of human ATP:Cob(I)alamin adenosyltransferase

Bobik, TA, Fan, C

Biochemistry 2008
Catalyst Activity

cob(I)yrinic acid a,c-diamide adenosyltransferase activity of 3xMMAB [mitochondrial matrix]

Orthologous Events
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