Catalyzes the hydrolytic deamination of adenosine to produce inosine (PubMed:19728741). Unlike mammalian adenosine deaminases, also catalyzes the deamination of 5'-methylthioadenosine (MTA), a by-product of polyamine biosynthesis, to produce 5'-methylthioinosine (MTI) (PubMed:19728741). Plays an essential role in the purine salvage pathway which allows the parasite to use host cell purines for the synthesis of nucleic acids (Probable). adenosine + H(+) + H2O = inosine + NH4(+) H(+) + H2O + S-methyl-5'-thioadenosine = NH4(+) + S-methyl-5'-thioinosine Binds 1 zinc ion per subunit. Inhibited by coformycin and methylthiocoformycin (MT-coformycin). kcat is 6.8 sec(-1) with adenosine as substrate (PubMed:19728741). kcat is 0.51 sec(-1) with 5'-methylthioadenosine as substrate (PubMed:19728741). Purine metabolism; purine nucleoside salvage. Belongs to the metallo-dependent hydrolases superfamily. Adenosine and AMP deaminases family.