title: Altered heat-lability of a fraction of glutathione reductase in aging human lens.
abstract: An unusually heat-labile fraction of glutathione reductase appears in human lens at about an age of 32 years. No such change was found in glucose 6-phosphate dehydrogenase nor in 3-phosphoglycerate kinase. The change is an intrinsic property of glutathione reductase. A greater proportion of the altered glutathione reductase was found in the core, the older part, of the lens. No evidence of a second band of activity was obtained after electrophoresis. Possible interpretations of the results, including errors of protein synthesis, production of a new isoenzyme and post-synthetic changes, are discussed.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D003545:Cysteine; D004591:Electrophoresis, Polyacrylamide Gel; D004592:Electrophoresis, Starch Gel; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism*; D006358:Hot Temperature; D006801:Humans; D007908:Lens, Crystalline / Q000201:enzymology*; D008875:Middle Aged; D009249:NADP; D010735:Phosphoglycerate Kinase / Q000378:metabolism
chemical_list: D009249:NADP; D005954:Glucosephosphate Dehydrogenase; D005980:Glutathione Reductase; D010735:Phosphoglycerate Kinase; D003545:Cysteine