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Amidohydrolase Superfamily

  1. Aimin Liu,
  2. Lu Huo

Published Online: 15 AUG 2014

DOI: 10.1002/9780470015902.a0020546.pub2



How to Cite

Liu, A. and Huo, L. 2014. Amidohydrolase Superfamily. eLS. .

Author Information

  1. Georgia State University, Atlanta, Georgia, USA

Publication History

  1. Published Online: 15 AUG 2014


The amidohydrolase superfamily is a structure-based cluster of enzymes that contain a sturdy and versatile triosephosphate isomerase (TIM)-like (β/α)8-barrel fold embracing the catalytic active site. To date, the amidohydrolase superfamily has grown into one of the largest families of enzymes, with tens of thousand of members catalysing a wide range of hydrolytic and nonhydrolytic metabolic reactions which are important in amino acid and nucleotide metabolism as well as biodegradation of agricultural and industrial compounds. Previously, the presence of a mono- or dinuclear d-block metal cofactor in the active site was thought to be one of the main characteristics of the members in this superfamily. However, recently new members containing a trinuclear metal cofactors or no cofactor at all were discovered. It has become apparent that activating a well-ordered water molecule by an active site residue for nucleophilic attack on the organic substrate is a common mechanistic feature for all members of the superfamily.

Key Concepts:

  • Amidohydrolase superfamily is one of the largest enzyme superfamilies performing a wide array of catalytic reactions.

  • All members in the family employ a TIM-barrel structural fold, although some of the amidohydrolase superfamily members present an imperfect barrel.

  • The vast majority, but not all, of the enzymes in this superfamily are metalloenzymes.

  • The hallmark of the catalytic mechanisms shared by these enzymes is to use an activated water molecule to attack the organic substrate.

  • The catalytic centre is diverse, with one, two, three or zero metal ion(s).


  • amidohydrolase;
  • metal cofactor;
  • TIM-barrel structural fold;
  • enzymology;
  • evolution