AMP deaminase plays a critical role in energy metabolism. AMP + H(+) + H2O = IMP + NH4(+) Binds 1 zinc ion per subunit. Purine metabolism; IMP biosynthesis via salvage pathway; IMP from AMP: step 1/1. Homotetramer. Present with 3910 molecules/cell in log phase SD medium. Belongs to the metallo-dependent hydrolases superfamily. Adenosine and AMP deaminases family.