Ribose. An oxidation product of glucose 6-phosphate in microsomal fraction.
An oxidative metabolism of glucose 6-phosphate was studied in rat liver microsomal fraction. Although radioactive 14CO2 was formed from [1-14C]glucose 6-phosphate in the microsomal fraction (Hino, Y., and Minakami, S. (1982) J. Biochem. (Tokyo) 92, 547-557), the formation was negligible when [2-14C]glucose 6-phosphate was used as a starting substrate. These results indicated an inability of the microsomal fraction to rearrange [2-14C]glucose 6-phosphate to form [1-14C] glucose 6-phosphate, and it was expected that a certain compound derived from glucose 6-phosphate accumulated as an end-product of the reaction. We, therefore, have tried to identify the product by high performance liquid chromatography, and found that ribose accumulated as the end-product. The formation of ribose was inhibited in the same manner as that of 14CO2 by antibodies against rat liver microsomal hexose-6-phosphate dehydrogenase, and the ratios of ribose to 14CO2 formed in the reaction were 0.5-0.8 on a molar basis. The finding of ribose formation further suggested the involvement of ribose phosphate isomerase and phosphatase activities in the reaction.
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003600:Cytosol / Q000378:metabolism; D019298:Glucose-6-Phosphate; D005958:Glucosephosphates / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism*; D010084:Oxidation-Reduction; D051381:Rats; D012266:Ribose / Q000302:isolation & purification / Q000378:metabolism*
D005958:Glucosephosphates; D019298:Glucose-6-Phosphate; D012266:Ribose