B C D How is it that smaller molecules move through a column

How is it that smaller molecules move through a column more opposite large molecules, whereas in gel the is true, and large molecules move more slowly than small molecules?

Solution

A.In gel filtration,the column matrix is made up of a resin containing small pores that are approximately the size of the proteins to be separated. Therefore, proteins that are larger than the pore size of the resin will not be able to enter the pores and will move out of the column fast as compared to small proteins that will spend more time in the pores and will come out of the column late while in SDS, all the proteins are negatively charged and the movement will depend on the size /mass of the proteins.Therefore larger proteins will take longer to move than smaller proteins as the mass of larger proteins is more than that of smaller proteins.

B.In 2D electrophoresis,electrophoresis is carried out in two dimensions.In the first dimension, proteins are separated according to their isoelectric point.In the second dimension electrophoresis that is perpendicular to the first, the proteins are separated according to the charge.Yes, it matters which electrophoresis is carried out first as 2D electrophoresis on separates proteins based on isoelectric point of proteins.So,it is important to first separate the proteins based on isoelectric point and then carry out the second electropheresis perpendicularly to separate proteins based on their mass.

C.We would place the protein under CATH hierarchical classification because under this classification,protein domain structures at grouped under four major levels i.e class(C), architecture(A), topology(T) and homologous superfamily (H).

D.Two distinct ways to elute an immunoprecipitated protein from the affinity resin are: