Question

Work out 9C and 9D using info given please. No additional info is needed.

Workout all parts of number 9. Explain in clear details on how to draw a gel, why and how to determine where the bands will be formed. 9. The following proteins were identified in a mixture. protein MW (kDa) 38 4.8 [MgSO.) resured to precious 45% 80% 65% 20% 30% 45% 6.8 9.50 5.3 115 a) What is meant by "salting out a protein using MgSO:? What happens on a molecular level? b) Draw a gel indicating proteins 1-6 order of elution in SDS-PAGE. Label where sample would start so I am clear on the validity of your answer. c) Draw their order of elution off of a a cation exchange column. d) Draw their order of elution off of a size exclusion column.

Answer 1

a. Salting out is a method of purification of protein with the help of electrolytes-non electrolytes interaction in which the non electrolytes (protein) become less soluble at higher salt concentration.

Salts are readily hydrolyzed in water hence when salt is added in a aqueous solution of non electrolyte i.e; the protein which contains both hydrophilic and hydrophobic amino acid part, the salt compete with the non electrolyte to bind with solvent molecule. Hence fewer water molecule is now available to bind with the protein, hence solute-solvent interaction becomes weaker than solute-solute interaction in case of protein. Hence salting out takes place.