Which statement describes the basis for separation of red fluorescent protein in column chromatography?

Which statement describes the basis for separation of red fluorescent protein in column chromatography?

• A. It separates proteins based on molecular weight.
• B. It separates based on hydrophobic character; the red protein binds in the unfolded state due to more hydrophobic residues.
• C. It separates proteins based on color.
• D. It uses antibody affinity.

Answer: (B)

In column chromatography, separation hinges on how proteins interact with the stationary phase. When the resin works by hydrophobic interactions, proteins with exposed hydrophobic surfaces will stick to the resin more strongly. The red fluorescent protein, if it becomes unfolded, reveals more hydrophobic residues on its surface, increasing its affinity for a hydrophobic column. Under the right conditions (often high salt to promote hydrophobic interactions), it binds; lowering the salt or changing the solvent weakens those interactions and allows the protein to elute. This makes hydrophobic character the key property being exploited for separation. Separating by molecular weight would rely on a size-based method, not on hydrophobicity. Using an antibody or ligand would be affinity chromatography, which targets a specific binding partner rather than general hydrophobicity. Color itself isn’t a mechanism by which chromatography separates molecules; the basis is the chemical or physical interactions with the resin. So describing the separation as driven by hydrophobic character, with binding enhanced when the protein is unfolded due to exposed hydrophobic residues, best captures the concept.

In column chromatography, separation hinges on how proteins interact with the stationary phase. When the resin works by hydrophobic interactions, proteins with exposed hydrophobic surfaces will stick to the resin more strongly. The red fluorescent protein, if it becomes unfolded, reveals more hydrophobic residues on its surface, increasing its affinity for a hydrophobic column. Under the right conditions (often high salt to promote hydrophobic interactions), it binds; lowering the salt or changing the solvent weakens those interactions and allows the protein to elute. This makes hydrophobic character the key property being exploited for separation.

Separating by molecular weight would rely on a size-based method, not on hydrophobicity. Using an antibody or ligand would be affinity chromatography, which targets a specific binding partner rather than general hydrophobicity. Color itself isn’t a mechanism by which chromatography separates molecules; the basis is the chemical or physical interactions with the resin. So describing the separation as driven by hydrophobic character, with binding enhanced when the protein is unfolded due to exposed hydrophobic residues, best captures the concept.