Molecular chaperones protect against glycation-induced inactivation of glucose-6-phosphate dehydrogenase.
Glucose-6-phosphate dehydrogenase is inactivated slowly by reaction with sugars (glycation), a process thought to be important in the development of diabetic complications. A major protein from the ocular lens, alpha-crystallin. which exhibits some chaperone-like properties, protects against this inactivation. The well-known molecular chaperone GroEL (chaperonin 60 from Escherichia coli) also protects. On a molar basis, alpha-crystallin is better than GroEL at protecting against glycation-induced inactivation of glucose-6-phosphate dehydrogenase. The relative amounts of enzyme/chaperone indicate that each molecule of alpha-crystallin binds two molecules of the damaged enzyme. This supports the view that alpha-crystallin has a chaperone-like structure as well as a chaperone-like function.
Ganea
E
E
Nuffield Laboratory of Ophthalmology, University of Oxford, UK.
Harding
J J
JJ
D018834:Chaperonin 60 / Q000378:metabolism; D003459:Crystallins / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D005954:Glucosephosphate Dehydrogenase / Q000037:antagonists & inhibitors*; D018832:Molecular Chaperones / Q000502:physiology*
D018834:Chaperonin 60; D003459:Crystallins; D018832:Molecular Chaperones; D005954:Glucosephosphate Dehydrogenase; D005947:Glucose