2. FLAG-tag is often introduced to a protein for Western blotting, immunoprecipitation, or recombinant protein purification. It consists of an amino acid sequence DYKDDDDK. When a FLAG-tag is introduced a recombinant protein, how would it affect the net charge of the recombinant protein when buffered at neutral pH?
(A) +4
(B)+1
(C)-2
(E) -5
(D)-3
答案：99
統計：A:0,B:0,C:0,D:0,E:0
難度：計算中