Catalyzes the hydrolytic deamination of adenosine and 2-deoxyadenosine. Plays an important role in purine metabolism and in adenosine homeostasis. Modulates signaling by extracellular adenosine, and so contributes indirectly to cellular signaling events. May act as a positive regulator of T-cell coactivation (By similarity). adenosine + H(+) + H2O = inosine + NH4(+) Binds 1 zinc ion per subunit. Belongs to the metallo-dependent hydrolases superfamily. Adenosine and AMP deaminases family.