When cystine is isolated after a protein is hydrolyzed,it is deduced that
A)2 cysteine amino acids are present in the protein.
B)the protein is linked by a disulfide bridge.
C)2 cysteine amino acids in the protein or proteins must be adjacent.
D)All of the above.

Question

Quizplus · Accepted Answer

The presence of cystine indicates that two cysteine amino acids were present in the protein and that the protein is linked by a disulfide bridge. The formation of cystine requires that two cysteine residues be adjacent to each other in the protein. Therefore, all of the options (A, B, and C) are correct.

When Cystine Is Isolated After a Protein Is Hydrolyzed,it Is