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. A number of isoforms are produced. Expressed in adult tissues such as aorta, heart, kidney, lung, muscle and thyroid. Weakly expressed in thyroid and not detected in liver. Belongs to the metallo-dependent hydrolases superfamily. Adenosine and AMP deaminases family. Extended N-terminus.