Tags: Enzyme.
In enzymology a guanosine phosphorylase (EC 2.4.2.15) is an enzyme that catalyzes the chemical reactionguanosine + phosphate guanine + alpha-D-ribose 1-phosphateThus the two substrates of this enzyme are guanosine and phosphate whereas its two products are guanine and alpha-D-ribose 1-phosphate.This enzyme belongs to the family of glycosyltransferases specifically the pentosyltransferases. The systematic name of this enzyme class is guanosine:phosphate alpha-D-ribosyltransferase.