Guanidinoacetate N-methyltransferase explained

guanidinoacetate N-methyltransferase
Ec Number:	2.1.1.2
Cas Number:	9029-75-8
Go Code:	0030731

Guanidinoacetate N-methyltransferase is an enzyme that catalyzes the chemical reaction and is encoded by gene GAMT located on chromosome 19p13.3.^[1]

S-adenosyl-L-methionine + guanidinoacetate

\rightleftharpoons S-adenosyl-L-homocysteine + creatine

Thus, the two substrates of this enzyme are S-adenosyl methionine and guanidinoacetate, whereas its two products are S-adenosylhomocysteine and creatine.

This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:N-guanidinoacetate methyltransferase. Other names in common use include GA methylpherase, guanidinoacetate methyltransferase, guanidinoacetate transmethylase, methionine-guanidinoacetic transmethylase, and guanidoacetate methyltransferase. This enzyme participates in glycine, serine and threonine metabolism and arginine and proline metabolism.

The protein encoded by this gene is a methyltransferase that converts guanidoacetate to creatine, using S-adenosylmethionine as the methyl donor. Defects in this gene have been implicated in neurologic syndromes and muscular hypotonia, probably due to creatine deficiency and accumulation of guanidinoacetate in the brain of affected individuals. Two transcript variants encoding different isoforms have been described for this gene.

Structural studies

As of late 2007, 7 structures have been solved for this class of enzymes, with PDB accession codes,,,,,, and .

See also

• Guanidinoacetate methyltransferase deficiency

Further reading

• Almeida LS . A prevalent pathogenic GAMT mutation (c.59G>C) in Portugal . Mol. Genet. Metab. . 91 . 1 . 1–6 . 2007 . 17336114 . 10.1016/j.ymgme.2007.01.005 . vanc. Vilarinho L . Darmin PS . 3 . Rosenberg . E.H. . Martinez-Muñoz . C. . Jakobs . C. . Salomons . G.S. .
• Morris AA . Guanidinoacetate methyltransferase deficiency masquerading as a mitochondrial encephalopathy . J. Inherit. Metab. Dis. . 30 . 1 . 100 . 2007 . 17171576 . 10.1007/s10545-006-0478-2 . vanc. Appleton RE . Power B . 3 . Isherwood . D. M. . Abernethy . L. J. . Taylor . R. W. . Turnbull . D. M. . Verhoeven . N. M. . Salomons . G. S. . 20768084 . free .
• Almeida LS . Overexpression of GAMT restores GAMT activity in primary GAMT-deficient fibroblasts . Mol. Genet. Metab. . 89 . 4 . 392–4 . 2007 . 16899382 . 10.1016/j.ymgme.2006.06.006 . vanc. Rosenberg EH . Martinez-Muñoz C . 3 . Verhoeven . N.M. . Vilarinho . L. . Jakobs . C. . Salomons . G.S. .
• Gerhard DS . The Status, Quality, and Expansion of the NIH Full-Length cDNA Project: The Mammalian Gene Collection (MGC) . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 . vanc. Wagner L . Feingold EA . 3 . Shenmen . CM . Grouse . LH . Schuler . G . Klein . SL . Old . S . Rasooly . R .
• Grimwood J . The DNA sequence and biology of human chromosome 19 . Nature . 428 . 6982 . 529–35 . 2004 . 15057824 . 10.1038/nature02399 . vanc. Gordon LA . Olsen A . 3 . Terry . Astrid . Schmutz . Jeremy . Lamerdin . Jane . Hellsten . Uffe . Goodstein . David . Couronne . Olivier . 2004Natur.428..529G . free .
• Strausberg RL . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . vanc. Feingold EA . Grouse LH . 3 . Derge . JG . Klausner . RD . Collins . FS . Wagner . L . Shenmen . CM . Schuler . GD . 2002PNAS...9916899M . free .
• Komoto J . Crystallization and preliminary x-ray diffraction studies of guanidinoacetate methyltransferase from rat liver . Acta Crystallogr. D . 55 . Pt 11 . 1928–9 . 2000 . 10531498 . 10.1107/S0907444999010318 . vanc. Huang Y . Hu Y . 3 . Takata . Yoshimi . Konishi . Kiyoshi . Ogawa . Hirofumi . Gomi . Tomoharu . Fujioka . Motoji . Takusagawa . Fusao . 1808/17175 . free .
• Chae YJ . The gene encoding guanidinoacetate methyltransferase (GAMT) maps to human chromosome 19 at band p13.3 and to mouse chromosome 10 . Genomics . 49 . 1 . 162–4 . 1998 . 9570966 . 10.1006/geno.1998.5236 . vanc. Chung CE . Kim BJ . 3 . Lee . MH . Lee . H .
• Jenne DE, Olsen AS, Zimmer M . The human guanidinoacetate methyltransferase (GAMT) gene maps to a syntenic region on 19p13.3, homologous to band C of mouse chromosome 10, but GAMT is not mutated in jittery mice . Biochem. Biophys. Res. Commun. . 238 . 3 . 723–7 . 1997 . 9325156 . 10.1006/bbrc.1997.9992 .
• Polyak K . A model for p53-induced apoptosis . Nature . 389 . 6648 . 300–5 . 1997 . 9305847 . 10.1038/38525 . vanc. Xia Y . Zweier JL . 3 . Kinzler . Kenneth W. . Vogelstein . Bert . 1997Natur.389..300P . 4429638 .
• Stöckler S . Guanidinoacetate methyltransferase deficiency: the first inborn error of creatine metabolism in man . Am. J. Hum. Genet. . 58 . 5 . 914–22 . 1996 . 8651275 . 1914613 . vanc. Isbrandt D . Hanefeld F . 3 . Schmidt . B . Von Figura . K .
• Isbrandt D, von Figura K . Cloning and sequence analysis of human guanidinoacetate N-methyltransferase cDNA . Biochim. Biophys. Acta . 1264 . 3 . 265–7 . 1996 . 8547310 . 10.1016/0167-4781(95)00184-0.
• Cantoni GL, Scarano E. 1954 . The formation of S-adenosylhomocysteine in enzymatic transmethylation reactions . J. Am. Chem. Soc. . 76 . 4744 . 10.1021/ja01647a081 . 18 .
• CANTONI GL, VIGNOS PJ . 1954 . Enzymatic mechanism of creatine synthesis . J. Biol. Chem. . 209 . 647 - 59 . 13192118 . 2 . 10.1016/S0021-9258(18)65492-4 . free .

External links

• PDBe-KB provides an overview of all the structure information available in the PDB for Human Guanidinoacetate N-methyltransferase

Notes and References

1. Web site: Entrez Gene: GAMT guanidinoacetate N-methyltransferase.