Effect of protein and peptide inhibitors on the activity of protein disulfide isomerase
| Autor: | Hiram F. Gilbert, Nihmat Morjana |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Molecular Sequence Data
Protein Disulfide-Isomerases Peptide Protein-disulfide reductase (glutathione) Biochemistry Binding Competitive chemistry.chemical_compound Animals Insulin Amino Acid Sequence Binding site Protein disulfide-isomerase Isomerases Peptide sequence chemistry.chemical_classification Chemistry Oxidative folding Proteins Glutathione Hormones Kinetics Liver Cattle Peptides Mathematics Cysteine |
| Zdroj: | Biochemistry. 30(20) |
| ISSN: | 0006-2960 |
| Popis: | The protein disulfide isomerase catalyzed reduction of insulin by glutathione is inhibited by peptides of various length and amino acid composition. Peptide inhibitors are competitive against insulin and noncompetitive against GSH, consistent with a sequential rather than a double displacement mechanism. Peptides of unrelated primary sequence that do not contain cysteine inhibit the GSH-insulin transhydrogenase activity of PDI, and the affinity of these peptides toward the enzyme is largely dependent on the peptide length rather than composition, hydrophobicity, or charge. Cysteine-containing peptides are 4-8-fold better inhibitors than non-cysteine-containing peptides of the same length, suggesting a cysteine-specific component to the interaction with the enzyme. Oxidized insulin chain B also inhibits the oxidative folding of reduced ribonuclease in a glutathione redox buffer with an inhibition constant that is comparable to that observed for the inhibition of insulin reduction, suggesting a similar if not identical binding site for the catalysis of oxidative protein folding and the reduction of insulin. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|