The Anfinsen experiment with Ribonuclease A

The Anfinsen experiment with Ribonuclease A established the general principle that denatured protein can spontaneously refold under appropriate conditions. In one experiment, RNAase A was simultaneously reduced with b-mercaptoethanol and denatured with urea. Residual bME was dialyzed away, and the protein was oxidized in air. Following oxidation, the urea was dialyzed away. The resulting protein was enzymatically inactive. Explain the lack of activity.     https://www.studyhelpus.com/Questions & Answers/ribonuclease-a/