How do covalent and non-covalent interactions affect protein migration in SDS-PAGE?

• A. Both covalent and non-covalent interactions are unaffected by SDS.
• B. Covalent interactions enhance protein migration speed.
• C. Covalent interactions are cleaved by SDS, while non-covalent interactions are not.
• D. Non-covalent interactions are disrupted by SDS, but covalent disulfide bonds require beta mercaptoethanol to be cleaved.

Answer: (D)