Question

Running size-exclusion chromatography, you have a protein elute at 25 minutes, with an approximate mass of 55kDa. You further examine the amino acid sequence of your protein and find that it contains 7 leucine amino acids. You decide to alter the amino acid sequence by replacing the 7 leucine amino acids with 7 isoleucines. What would be the approximate time the new protein would elute on the next size exclusion run?

A) 10 minutes
B) 20 minutes
C) 25 minutes
D) 30 minutes
E) 40 minutes

Answer 1

The new protein is expected to elute at a similar time, around C) 25 minutes. Hence, C) is correct.

Step-by-step explanation:

Size-exclusion chromatography is a method used to separate proteins based on their size. In this method, proteins are eluted from a column based on their size, with smaller proteins eluting later and larger proteins eluting earlier. In this case, the protein with a mass of 55kDa eluted at 25 minutes.

When you replace the 7 leucine amino acids with 7 isoleucines, the overall size and mass of the protein will not change significantly. Therefore, the new protein is expected to elute at a similar time, around 25 minutes.