Final answer:
To isolate thiol-containing proteins, affinity chromatography is the best choice, as it utilizes the specific interactions between proteins and a ligand on the stationary phase that targets thiol groups.
Step-by-step explanation:
To isolate thiol-containing proteins, the most appropriate chromatography technique is affinity chromatography. This method exploits the specific interactions between a ligand immobilized on a stationary phase and the protein of interest that has an affinity for the ligand. A common approach for targeting thiol groups involves using a thiol-specific reagent coupled to a chromatography matrix, which selectively binds to thiol-containing proteins. Once non-bound proteins are washed away, the target proteins can be eluted using a reducing agent that disrupts the thiol-ligand interaction.
In comparison, ion exchange chromatography separates proteins based on charge, size exclusion chromatography separates based on size, and reverse phase chromatography separates primarily based on hydrophobicity. Although techniques like reverse phase chromatography could also be used after modifications of the thiol groups, affinity chromatography is the most suitable choice when referring to the direct isolation of native thiol-containing proteins.