Reduction of ribonuclease by glutathione at elevated temperatures: the molecular mechanism.
1. The mechanism of the reaction between ribonuclease and GSH at elevated temperatures has been studied by using N-(4-dimethylamino-3,5-dinitrophenyl)-maleimide to label the reduced ribonuclease. 2. After incubation for 2hr. at 35 degrees , enzymically active ribonuclease was recovered; at 50.8 degrees half of the initial ribonuclease was recovered as enzymically active ribonuclease and half as reduced labelled ribonuclease; at 55 degrees all of the initial ribonuclease was recovered in the labelled form. 3. It was inferred that the rate-limiting step was the reduction of the first disulphide bond in any one molecule. This was followed by rapid reduction of the other bonds in the same molecule.
D000596:Amino Acids / Q000032:analysis; D005978:Glutathione / Q000378:metabolism*; D008298:Maleates / Q000494:pharmacology; D012260:Ribonucleases / Q000378:metabolism*; D013440:Sulfides / Q000378:metabolism; D013696:Temperature
D000596:Amino Acids; D008298:Maleates; D013440:Sulfides; D012260:Ribonucleases; D005978:Glutathione