Which statement is true about SDS-PAGE of proteins?
A)The migration order for proteins in SDS-PAGE is the same as the order in gel filtration because both are sieving techniques.
B)Some proteins migrate toward the anode and others toward the cathode.
C)The rate of migration is inversely proportional to the logarithm of the protein's mass.
D)SDS-PAGE is purely an analytic technique and is not used to purify proteins.

Question

Quizplus · Accepted Answer

The rate of migration in SDS-PAGE is directly proportional to the logarithm of the protein's mass due to the uniform negative charge imparted by the SDS detergent. This means smaller proteins will migrate faster and larger proteins will migrate slower, allowing for separation based on size. The migration order in gel filtration is based on the size and shape of the protein, not charge, so it is not the same as SDS-PAGE. Proteins in SDS-PAGE all migrate towards the anode due to the negative charge, not towards both the anode and cathode. SDS-PAGE can also be used as a purification technique, as proteins can be eluted from the gel after separation.

Which Statement Is True About SDS-PAGE of Proteins