Amidase structure and mechanism

Amidase enzymes catalyze the hydrolysis of amide bonds with considerable divergence noted within the family with respect to substrate spedficity. All amidase enzymes, however, maintain the core a,p,a structure, where the topologies of the C and N terminal halves are similar. 

Aliphatic amidase enzymes demonstrate sequence similarity to the nitrilase superfamily thus indicating some form of evolutionary relationship. These amidases contain a Glu-Lys-Cys catalytic triad and exist as homotetrameric or homohexameric sttuctures that function via a ping-pong (bi-bi) reaction mechanism [60, 61]. 

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