Nucleoside phosphorylase <p>The following phosphorylases belong to the same family:</p><p> <ul><li>Purine nucleoside phosphorylase (<db_xref db="EC" dbkey="2.4.2.1"/>) (PNP) from most bacteria (gene deoD), which catalyses the cleavage of guanosine or inosine to respective bases and sugar-1-phosphate molecules [<cite idref="PUB00000763"/>].</li><li>Uridine phosphorylase (<db_xref db="EC" dbkey="2.4.2.3"/>) (UdRPase) from bacteria (gene udp) and mammals, which catalyses the cleavage of uridine into uracil and ribose-1-phosphate, the products of the reaction are used either as carbon and energy sources or in the rescue of pyrimidine bases for nucleotide synthesis [<cite idref="PUB00002902"/>].</li><li>5'-methylthioadenosine phosphorylase (<db_xref db="EC" dbkey="2.4.2.28"/>) (MTA phosphorylase) from <taxon tax_id="2287">Sulfolobus solfataricus</taxon> [<cite idref="PUB00002872"/>].</li></ul> </p><p>It should be noted that mammalian and some bacterial PNP as well as eukaryotic MTA phosphorylase belong to a different family of phosphorylases.</p>