The route of non-enzymic and enzymic breakdown of 5-phosphoribosyl 1-pyrophosphate to ribose 1-phosphate.
Spontaneous decomposition of 5-phosphoribosyl 1-pyrophosphate at pH 5.5 was established to occur as follows: 5-Phosphoribosyl 1-pyrophosphate----5-phosphoribosyl 1,2-(cyclic)phosphate----ribose 1-phosphate----ribose Enzymic degradation of 5-phosphoribosyl 1-pyrophosphate by alkaline phosphatase from calf intestine and by acid phosphatases from potato and Aspergillus niger was found to proceed according to this pathway within the pH range 2.5-7.4 with accumulation of ribose 1-phosphate. In the case of alkaline phosphatase, Mg2+ ions inhibit the pyrophosphorolysis of 5-phosphoribosyl 1-pyrophosphate and stimulate the hydrolysis of ribose 1-phosphate.
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa.
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Jezewska
D000135:Acid Phosphatase / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001234:Aspergillus niger / Q000201:enzymology; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007041:Hypoxanthine Phosphoribosyltransferase / Q000378:metabolism; D007288:Inosine / Q000096:biosynthesis; D007422:Intestines / Q000201:enzymology; D010754:Phosphoribosyl Pyrophosphate / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D012267:Ribosemonophosphates / Q000378:metabolism*; D011198:Solanum tuberosum
D012267:Ribosemonophosphates; C031154:ribose 1-phosphate; D007288:Inosine; D010754:Phosphoribosyl Pyrophosphate; D007041:Hypoxanthine Phosphoribosyltransferase; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D010744:Phosphoric Monoester Hydrolases