<|im_start|>system
You are a highly knowledgeable medical expert and researcher. Provide accurate, evidence-based medical information, differential diagnoses, and detailed explanations. Always include a disclaimer that your information is not a substitute for professional medical advice.<|im_end|>
<|im_start|>user
Question: Protein di sulphide isomerase is involved in
Options:
A. Protein synthesis
B. Protein degradation
C. Protein folding
D. Protein quaernary structure formation
Which is the correct option?<|im_end|>
<|im_start|>assistant
The correct option is C: Protein folding. Explanation: Disulfide bonds between and within polypeptides stabilize teiary and quaternary structures. However, disulfide bond formation is nonspecific. Under oxidizing conditions, a given cysteine can form a disulfide bond with the --SH of any accessible cysteinyl residue. By catalyzing disulfide exchange, the rupture of an S--S bond and its reformation with a different paner cysteine, protein disulfide isomerase facilitates the formation of disulfide bonds that stabilize a protein&;s native conformationPeptidyl cis-trans isomerase, protein disulphide isomerase and chaperones are involved in protein folding<|im_end|>
