Defective MMAB does not transfer adenosyl group from ATP to B12s

Stable Identifier
R-HSA-3322125
Type
Reaction [transition]
Species
Homo sapiens
Compartment
mitochondrial matrix
ReviewStatus
5/5
Locations in the PathwayBrowser
Expand all
General
SVG | 
PNG
Low
Medium
High
 | PPTX  | SBGN
Defective MMAB does not transfer adenosyl group from ATP to B12s
Click the image above or here to open this reaction in the Pathway Browser
The layout of this reaction may differ from that in the pathway view due to the constraints in pathway layout
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 (cblB aka methylmalonic aciduria type B or vitamin B12-responsive methylmalonicaciduria of cblB complementation type; MIM:251110). Affected individuals have methylmalonic aciduria and episodes of 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). The point mutations R186W, R191W and E193K result in very low levels of AdoCbl (Dobson et al. 2002).
Literature References
PubMed ID Title Journal Year
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, Wai, T, Leclerc, D, Wilson, A, Wu, X, Doré, C, Hudson, T, Rosenblatt, DS, Gravel, RA

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

Fan, C, Bobik, TA

Biochemistry 2008
12514191 Identification of the human and bovine ATP:Cob(I)alamin adenosyltransferase cDNAs based on complementation of a bacterial mutant

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

J. Biol. Chem. 2003
Participants
Input
Participates
as an event of
Catalyst Activity

corrinoid adenosyltransferase activity of MMAB mutants [mitochondrial matrix]

Physical Entity
MMAB mutants [mitochondrial matrix] (Homo sapiens)
Activity
corrinoid adenosyltransferase activity (GO:0008817)
Normal reaction
MMAB adenosylates cob(I)alamin (Homo sapiens)
Functional status

Loss of function of MMAB mutants [mitochondrial matrix]

Normal Entity
Disease Entity
Status
Disease
Name Identifier Synonyms
methylmalonic acidemia DOID:14749 METHYLMALONICACIDURIA DUE TO METHYLMALONIC CoA MUTASE deficiency, METHYLMALONIC ACIDURIA, mut TYPE, METHYLMALONIC ACIDEMIA, cblB TYPE, methylmalonic aciduria mut type, METHYLMALONICACIDURIA, vitamin B12-RESPONSIVE, DUE TO DEFECT IN SYNTHESIS OF ADENOSYLCOBALAMIN--cbl B, methylmalonic aciduria cblB type, METHYLMALONIC ACIDURIA DUE TO METHYLMALONYL-CoA MUTASE DEFICIENCY, METHYLMALONIC ACIDURIA, VITAMIN B12-RESPONSIVE, DUE TO DEFECT IN SYNTHESIS OF ADENOSYLCOBALAMIN, cblA TYPE, methylmalonic aciduria, METHYLMALONIC ACIDURIA, VITAMIN B12-RESPONSIVE, DUE TO DEFECT IN SYNTHESIS OF ADENOSYLCOBALAMIN, cblB TYPE, METHYLMALONIC ACIDEMIA, cblA TYPE, METHYLMALONICACIDURIA, vitamin B12-RESPONSIVE, DUE TO DEFECT IN SYNTHESIS OF ADENOSYLCOBALAMIN--cbl A
Cross References
Mondo
Authored
Jassal, B  (2013-05-03)
Reviewed
Watkins, D  (2013-08-14)
Created
Jassal, B  (2013-05-03)
Cite Us!