Amidase Explained

amidase
Ec Number:3.5.1.4
Cas Number:9012-56-0
Go Code:0004040
Symbol:Amidase
Amidase
Pfam:PF01425
Interpro:IPR000120
Prosite:PDOC00494
Scop:1ocm
Opm Family:55
Opm Protein:1mt5
Membranome Superfamily:325

In enzymology, an amidase (acylamidase, acylase (misleading), amidohydrolase (ambiguous), deaminase (ambiguous), fatty acylamidase, N-acetylaminohydrolase (ambiguous)) is an enzyme that catalyzes the hydrolysis of an amide. In this way, the two substrates of this enzyme are an amide and H2O, whereas its two products are monocarboxylate and NH3.

This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amides. The systematic name of this enzyme class is acylamide amidohydrolase. Other names in common use include acylamidase, acylase, amidohydrolase, deaminase, fatty acylamidase, and N-acetylaminohydrolase. This enzyme participates in 6 metabolic pathways: urea cycle and metabolism of amino groups, phenylalanine metabolism, tryptophan metabolism, cyanoamino acid metabolism, benzoate degradation via coa ligation, and styrene degradation.

Amidases contain a conserved stretch of approximately 130 amino acids known as the AS sequence. They are widespread, being found in both prokaryotes and eukaryotes. AS enzymes catalyse the hydrolysis of amide bonds (CO-NH2), although the family has diverged widely with regard to substrate specificity and function. Nonetheless, these enzymes maintain a core alpha/beta/alpha structure, where the topologies of the N- and C-terminal halves are similar. AS enzymes characteristically have a highly conserved C-terminal region rich in serine and glycine residues, but devoid of aspartic acid and histidine residues, therefore they differ from classical serine hydrolases. These enzymes possess a unique, highly conserved Ser-Ser-Lys catalytic triad used for amide hydrolysis, although the catalytic mechanism for acyl-enzyme intermediate formation can differ between enzymes.[1]

Examples of AS signature-containing enzymes include:

Structural studies

As of late 2018, 162 structures have been solved for this family, which can be accessed at the Pfam .

Further reading

Notes and References

  1. Valiña AL, Mazumder-Shivakumar D, Bruice TC . Probing the Ser-Ser-Lys catalytic triad mechanism of peptide amidase: computational studies of the ground state, transition state, and intermediate . Biochemistry . 43 . 50 . 15657–72 . December 2004 . 15595822 . 10.1021/bi049025r .
  2. Wei BQ, Mikkelsen TS, McKinney MK, Lander ES, Cravatt BF . A second fatty acid amide hydrolase with variable distribution among placental mammals . J. Biol. Chem. . 281 . 48 . 36569–78 . December 2006 . 17015445 . 10.1074/jbc.M606646200 . free .
  3. Shin S, Lee TH, Ha NC, Koo HM, Kim SY, Lee HS, Kim YS, Oh BH . Structure of malonamidase E2 reveals a novelSer-cisSer-Lys catalytic triad in a new serine hydrolase fold that is prevalent in nature . EMBO J. . 21 . 11 . 2509–16 . June 2002 . 12032064 . 126024 . 10.1093/emboj/21.11.2509 .
  4. Kwak JH, Shin K, Woo JS, Kim MK, Kim SI, Eom SH, Hong KW . Expression, purification, and crystallization of glutamyl-tRNA(Gln) specific amidotransferase from Bacillus stearothermophilus . Mol. Cells . 14 . 3 . 374–81 . December 2002 . 12521300 .