Which of the following bonds or interactions is/are possible contributors to the stability of the tertiary structure of a globular protein?
A. Peptide bonds between a metal ion cofactor and a histidine residue
B. Hydrophobic interactions between histidine and tryptophan R groups.
C. Covalent disulfide cross-links between 2 methionine residues.
D. Hydrogen bonds between serine residues and the aqueous surroundings.
E. All of the above contribute.