Methylmalonyl-CoA mutase

Methylmalonyl CoA mutase
Rendering based on PDB 2XIJ.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 2XIJ, 2XIQ, 3BIC
Identifiers
Symbols	MUT; MCM
External IDs	OMIM: 609058 MGI: 97239 HomoloGene: 20097 GeneCards: MUT Gene
EC number	5.4.99.2
Gene Ontology Molecular function • methylmalonyl-CoA mutase activity • cobalamin binding • metal ion binding • modified amino acid binding Cellular component • mitochondrion • mitochondrial matrix Biological process • fatty acid beta-oxidation • post-embryonic development • short-chain fatty acid catabolic process • cellular lipid metabolic process • small molecule metabolic process • homocysteine metabolic process Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	4594	17850
Ensembl	ENSG00000146085	ENSMUSG00000023921
UniProt	P22033	P16332
RefSeq (mRNA)	NM_000255	NM_008650
RefSeq (protein)	NP_000246	NP_032676
Location (UCSC)	Chr 6: 49.4 – 49.43 Mb	Chr 17: 40.93 – 40.96 Mb
PubMed search	[1]	[2]

methylmalonyl-CoA mutase
Identifiers
EC number	5.4.99.2
CAS number	9023-90-9
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / EGO
Search PMC articles PubMed articles NCBI proteins

Methylmalonyl Coenzyme A mutase, also known as MCM is an enzyme that catalyzes the isomerization of methylmalonyl-CoA to succinyl-CoA and it is involved in key metabolic pathways. It requires a vitamin B₁₂-derived prosthetic group, adenosylcobalamin, to function.

Function

The substrate of methylmalonyl-CoA mutase, methylmalonyl-CoA, is primarily derived from propionyl-CoA, a substance formed from the catabolism and digestion of isoleucine, valine, threonine, methionine, thymine, cholesterol, or odd-chain fatty acids.

The product of the enzyme, succinyl-CoA, is a key molecule of the TCA cycle.

MCM resides in the mitochondria, where a number of substances, including the branched-chain amino acids isoleucine and valine, as well as methionine, threonine, thymine and odd-chain fatty acids, are metabolized via methylmalonate semialdehyde (MMlSA) or propionyl-CoA (Pr-CoA) to a common compound - methylmalonyl-CoA (MMl-CoA).

Human Genetics

The gene encoding for this enzyme in humans is known as MUT.

Pathology

A deficiency of this enzyme is responsible for an inherited disorder of metabolism, Methylmalonyl-CoA mutase deficiency, which is one of the causes of methylmalonic acidemia.

Mechanism

MUT reaction mechanism begins with homolytic cleavage of AdoB12's C-Co(III) bond, the C and Co atoms each acquire one of the electrons that formed the cleaved electron pair bond. The Co ion, therefore, fluctuates between its Co(III) and Co(II) oxidation states [the two states are spectroscopically distinguishable: Co(III) is red and diamagnetic (no unpaired electrons), whereas Co(II) is yellow and paramagnetic (unpaired electrons)]. Hence, the role of coenzyme B-12 in the catalytic process is that of a reversible free radical generator. The C-Co(III) bond is well suited to this function because it is inherently weak (dissociation energy = 109 kJ/mol) and appears to be further weakened through steric interactions with the enzyme. A homolytic cleavage reaction is unusual in biology; most other biological bond cleavage reactions occur via heterolytic cleavage (in which the electron pair forming the cleaved bond is fully acquired by one of the separating atoms).

See also

• MMAA
• MMAB
• MMACHC
• MMADHC

Further reading

• Ledley FD, Rosenblatt DS (1997). "Mutations in mut methylmalonic acidemia: clinical and enzymatic correlations.". Hum. Mutat. 9 (1): 1–6. doi:10.1002/(SICI)1098-1004(1997)9:1<1::AID-HUMU1>3.0.CO;2-E. PMID 8990001. 
• Ludwig ML, Matthews RG (1997). "Structure-based perspectives on B12-dependent enzymes.". Annu. Rev. Biochem. 66: 269–313. doi:10.1146/annurev.biochem.66.1.269. PMID 9242908. 
• Lubrano R, Elli M, Rossi M, et al. (2007). "Renal transplant in methylmalonic acidemia: could it be the best option? Report on a case at 10 years and review of the literature.". Pediatr. Nephrol. 22 (8): 1209–14. doi:10.1007/s00467-007-0460-z. PMID 17401587. 
• Frenkel EP, Kitchens RL (1978). "Intracellular localization of hepatic propionyl-CoA carboxylase and methylmalonyl-CoA mutase in humans and normal and vitamin B12 deficient rats.". Br. J. Haematol. 31 (4): 501–13. doi:10.1111/j.1365-2141.1975.tb00885.x. PMID 24458. 
• Crane AM, Jansen R, Andrews ER, Ledley FD (1992). "Cloning and expression of a mutant methylmalonyl coenzyme A mutase with altered cobalamin affinity that causes mut- methylmalonic aciduria.". J. Clin. Invest. 89 (2): 385–91. doi:10.1172/JCI115597. PMC 442864. PMID 1346616. 
• Crane AM, Martin LS, Valle D, Ledley FD (1992). "Phenotype of disease in three patients with identical mutations in methylmalonyl CoA mutase.". Hum. Genet. 89 (3): 259–64. doi:10.1007/BF00220536. PMID 1351030. 
• Raff ML, Crane AM, Jansen R, et al. (1991). "Genetic characterization of a MUT locus mutation discriminating heterogeneity in mut0 and mut- methylmalonic aciduria by interallelic complementation.". J. Clin. Invest. 87 (1): 203–7. doi:10.1172/JCI114972. PMC 295026. PMID 1670635. 
• Jansen R, Ledley FD (1990). "Heterozygous mutations at the mut locus in fibroblasts with mut0 methylmalonic acidemia identified by polymerase-chain-reaction cDNA cloning.". Am. J. Hum. Genet. 47 (5): 808–14. PMC 1683687. PMID 1977311. 
• Nham SU, Wilkemeyer MF, Ledley FD (1991). "Structure of the human methylmalonyl-CoA mutase (MUT) locus.". Genomics 8 (4): 710–6. doi:10.1016/0888-7543(90)90259-W. PMID 1980486. 
• Ledley FD, Lumetta M, Nguyen PN, et al. (1988). "Molecular cloning of L-methylmalonyl-CoA mutase: gene transfer and analysis of mut cell lines.". Proc. Natl. Acad. Sci. U.S.A. 85 (10): 3518–21. doi:10.1073/pnas.85.10.3518. PMC 280243. PMID 2453061. 
• Jansen R, Kalousek F, Fenton WA, et al. (1989). "Cloning of full-length methylmalonyl-CoA mutase from a cDNA library using the polymerase chain reaction.". Genomics 4 (2): 198–205. doi:10.1016/0888-7543(89)90300-5. PMID 2567699. 
• Fenton WA, Hack AM, Kraus JP, Rosenberg LE (1987). "Immunochemical studies of fibroblasts from patients with methylmalonyl-CoA mutase apoenzyme deficiency: detection of a mutation interfering with mitochondrial import.". Proc. Natl. Acad. Sci. U.S.A. 84 (5): 1421–4. doi:10.1073/pnas.84.5.1421. PMC 304442. PMID 2881300. 
• Zoghbi HY, O'Brien WE, Ledley FD (1989). "Linkage relationships of the human methylmalonyl CoA mutase to the HLA and D6S4 loci on chromosome 6.". Genomics 3 (4): 396–8. doi:10.1016/0888-7543(88)90135-8. PMID 2907507. 
• Kolhouse JF, Utley C, Allen RH (1980). "Isolation and characterization of methylmalonyl-CoA mutase from human placenta.". J. Biol. Chem. 255 (7): 2708–12. PMID 6102092. 
• Fenton WA, Hack AM, Willard HF, et al. (1982). "Purification and properties of methylmalonyl coenzyme A mutase from human liver.". Arch. Biochem. Biophys. 214 (2): 815–23. doi:10.1016/0003-9861(82)90088-1. PMID 6124211. 
• Qureshi AA, Crane AM, Matiaszuk NV, et al. (1994). "Cloning and expression of mutations demonstrating intragenic complementation in mut0 methylmalonic aciduria.". J. Clin. Invest. 93 (4): 1812–9. doi:10.1172/JCI117166. PMC 294249. PMID 7909321. 
• Crane AM, Ledley FD (1994). "Clustering of mutations in methylmalonyl CoA mutase associated with mut- methylmalonic acidemia.". Am. J. Hum. Genet. 55 (1): 42–50. PMC 1918235. PMID 7912889. 
• Janata J, Kogekar N, Fenton WA (1998). "Expression and kinetic characterization of methylmalonyl-CoA mutase from patients with the mut- phenotype: evidence for naturally occurring interallelic complementation.". Hum. Mol. Genet. 6 (9): 1457–64. doi:10.1093/hmg/6.9.1457. PMID 9285782. 

External links

• GeneReviews/NIH/NCBI/UW entry on Methylmalonic Acidemia
• Methylmalonyl-CoA Mutase at the US National Library of Medicine Medical Subject Headings (MeSH)