Enzyme-to-enzyme channeling in the early steps of glycolysis in rat pancreatic islets.
The enzyme-to-enzyme channeling of metabolic intermediates is not an uncommon process. The present review draws attention to recent experimental work documenting, in rat pancreatic islets, the enzyme-to-enzyme channeling of alpha-D-glucose 6-phosphate between hexokinase isoenzyme(s), mainly glucokinase, and phosphoglucoisomerase. Likewise, the possible enzyme-to-enzyme channeling of beta-D-fructose 6-phosphate between phosphoglucoisomerase and phosphofructokinase is briefly evoked. These considerations are relevant to the anomeric specificity of D-glucose metabolism, even in islets exposed to equilibrated D-glucose, to the perturbation of such an anomeric specificity in the phenomenon of so-called B-cell glucotoxicity, and to the correct interpretation of 3HOH generation from D-[2-(3H)]glucose.
Malaisse
Willy J
WJ
Laboratory of Experimental Hormonology, Brussels Free University, Brussels, Belgium. malaisse@ulb.ac.be
Zhang
Ying
Y
Sener
Abdullah
A
D000818:Animals; D004798:Enzymes / Q000378:metabolism*; D005636:Fructosephosphates / Q000378:metabolism; D005941:Glucokinase / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D019298:Glucose-6-Phosphate / Q000378:metabolism; D005956:Glucose-6-Phosphate Isomerase / Q000378:metabolism; D006019:Glycolysis; D006593:Hexokinase / Q000378:metabolism; D007515:Islets of Langerhans / Q000201:enzymology* / Q000378:metabolism; D025221:Phosphofructokinases / Q000378:metabolism; D051381:Rats; D013379:Substrate Specificity
D004798:Enzymes; D005636:Fructosephosphates; D019298:Glucose-6-Phosphate; C027618:fructose-6-phosphate; D025221:Phosphofructokinases; D006593:Hexokinase; D005941:Glucokinase; D005956:Glucose-6-Phosphate Isomerase; D005947:Glucose