Question

You want to isolate a functional integral membrane protein from the cell to study its channel activity. What method would you use to isolate the integral membrane potential?

By adding SDS

By using Beta-mercaptoethanol

By boiling

By using a mild-detergent

By adding high concentration of salt

Answer 1

The answer is By adding a mild detergent. The deteregent distupts the lipid membrane, it helps to extract a protein in active form.

By adding SDS - when you add SDS, it binds to protein and distrubs the overall charge, - it leads to precepitation of inactive protein.

By using Beta-mercaptoethanol - It disrupts the disulphide bonds - it leads to precepitation of inactive protein.

By boiling - It distrubs the all bonds and it leads to precepitation of denatured protein.

By adding high concetration of salt - Under low slat concentration the solubility of protein lies at maxmium, when the salt is added to the solution, it decreasesthe solubility of protein and helps in the protein precipitation. This process is reffered as Salting in.