Protein electrophoresis
up vote
1
down vote
favorite
1
Three proteins A, B and C of equal molecular weight are being investigated in a study. They contain six, four and four cysteine residues respectively. Only Proteins A and B were treated with β-mercaptoethanol (which reduces disulphide bond) and heated in boiling water bath for a few minutes. Which of the following is expected in the SDS PAGE gel run? a. Protein C will move fastest. b. Protein B will move fastest. c. Proteins A and B will move at the same speed but faster than C. d. Proteins B and C will move at the same speed. Before knowing the answer the I thought the answer would be b. Because as Protein A has the most no. of amino acids so it will be behind Protein B and C for sure. And for protein B and C, as Protein B has been in a reducing environment it will not form disulfide bridges...