Question

What is the order of elution of the following proteins from a Sephadex G50 column: catalase (222 kDa), α-chymotrypsin (21.6 kDa), concanavalin B (42.5 kDa), lipase (6.7 kDa), myoglobin (16.9 kDa), fibrinogen (340 kDa). Give a brief explanation.

Answer 1

The order of elution from a Sephadex G50 column depends on the size exclusion limit of the resin and the molecular weight of the protein. Sephadex G50 is a gel filtration resin that separates proteins based on their size.

The proteins will elute in order of increasing molecular weight because larger proteins are excluded from the pores of the resin and elute first, while smaller proteins can enter the pores and take longer to elute.

Based on the given molecular weights, the order of elution would be as follows:

lipase (6.7 kDa) → α-chymotrypsin (21.6 kDa) → myoglobin (16.9 kDa) → concanavalin B (42.5 kDa) → catalase (222 kDa) → fibrinogen (340 kDa)

Therefore, lipase would elute first followed by α-chymotrypsin, myoglobin, concanavalin B, catalase, and finally fibrinogen.