purine-nucleoside phosphorylase activity S-methyl-5-thioadenosine phosphorylase activity https://github.com/geneontology/go-ontology/issues/30193 methylthioadenosine phosphorylase activity methylthioadenosine nucleoside phosphorylase activity S-methyl-5-thioadenosine:phosphate S-methyl-5-thio-alpha-D-ribosyl-transferase activity MetaCyc:5-METHYLTHIOADENOSINE-PHOSPHORYLASE-RXN MTA phosphorylase activity MTAPase activity 5'-methylthioadenosine:phosphate methylthio-D-ribosyl-transferase activity Reactome:R-HSA-1237160 5'-methylthioadenosine phosphorylase activity RHEA:11852 MeSAdo/Ado phosphorylase activity MeSAdo phosphorylase activity 5'-deoxy-5'-methylthioadenosine phosphorylase activity EC:2.4.2.28 molecular_function GO:0017061 Catalysis of the reaction: 5'-methylthioadenosine + phosphate = adenine + 5-methylthio-D-ribose 1-phosphate.