Disulfide bonds in proteins are formed between the side chains of cysteine amino acids. When two cysteine molecules are brought close together in the folding process of a protein, their sulfhydryl (-SH) groups can undergo an oxidation reaction to form a covalent bond, creating a disulfide bridge (—S—S—) linkage. This bond is important for stabilizing the tertiary and quaternary structures of proteins.
Problem:
Which amino acid has a side chain that can form a disulfide bond?
A) Valine
B) Cysteine
C) Leucine
D) Serine