Center for Bioinformatics
Oxidoreductases | Transferases | Hydrolases | Lyases | Isomerases | Ligases

Basic Information

Enzyme Number

Official Name

methionine adenosyltransferase

Name from literature

methionine adenosyl transferase

Pathway from literature

methionine metabolism

Pathway from KEGG

Metabolism of Other Amino Acids; Selenoamino acid metabolism; map00450

Amino Acid Metabolism; Methionine metabolism; map00271


Human (9606)

Genome localization

10q22[4143 ], 5q34-q35[27430 ],

Rate-limiting Description

"Because methionine adenosyl transferase (MAT) is the rate-limiting enzyme of the pathway, we examined the expression of a lung epithelial isoform of MAT 2A in hyperoxia." (16413417)

Regulatory Information

Upstream transcription factor


Regulatory type


regulatory enzyme;

"The activity of L-methionine S-adenosyltransferase (MAT), a regulatory enzyme of S-adenosylmethionine biosynthesis, was investigated in erythrocytes of 21 patients with ALS, spinal cord specimens of 7 ALS patients, and matched controls." (10415148)

transcriptional factor;Sp1(6667)

"Supershift studies coupled with analysis of proteins bound to the proximal promoter suggest that low levels of expression of Sp2 and Sp3 in normal T cells may be responsible for the difference in the in vitro promoter activity between normal and leukemic cells. Mutation of the key Sp1 site equally reduced the in vivo promoter activity in normal and malignant T cells; by contrast, it had significantly different effects on protein-DNA interactions in normal and leukemic T cells. Together, the data support the idea that differences in protein-DNA interactions may contribute to significant differences in MAT2A regulation in normal and malignant cells." (11476892)





Gene ontology

Gene ontology

GO:0006520 (P) amino acid metabolic process [Q00266 ];
GO:0000287 (F) magnesium ion binding [A8K455, A8K511, Q00266, P31153 ];
GO:0050897 (F) cobalt ion binding [A8K511, Q00266, P31153 ];
GO:0030955 (F) potassium ion binding [A8K455, A8K511, Q00266, P31153 ];
GO:0006730 (P) one-carbon compound metabolic process [A8K455, A8K511, Q00266, P31153 ];
GO:0005524 (F) ATP binding [A8K455, A8K511, Q00266, P31153 ];
GO:0004478 (F) methionine adenosyltransferase activity [A8K455, A8K511, Q00266, P31153 ];

Tissue expression

Tissue From HPRD

Liver [02013 ];
Lymphocyte [05701 ];
Ubiquitous [03275 ];

Tissue specificity

Expressed in liver [Q00266 ];

Disease relevance


Defects in MAT1A are a cause of a form of hypermethioninemia [MIM:250850];
also called MAT I/III deficiency. The disease is characterized by fetid breath and dimethylsulfide excretion. Most mutations are transmitted in an autosomal recessive manner, but autosomal dominant inheritance has also been observed. The clinical consequences of hypermethioninemia are poorly understood. In some individuals, hypermethioninemia is apparently benign;
in others, association of neurological problems with null mutations has been observed [Q00266 ];



A8K455; A8K511; B4DEX8; P31153; Q00266

Entrez Gene

27430; 4143


02013; 05701; 03275

  Copyright 2009, Center for Bioinformatics 
  Last Modified: 2009-03-24  
  Design by Zhao Min