1. (8 pt) DNA polymerase makes close contact with the minor groove during DNAreplication, while the helix-turn-helix (HTH) motifs of the CRP recognize their bindingsites by making close contact with the major groove. Answer the questions below. A. What is the purpose of making contacts with the minor groove during replication (2pts)? Why not making contacts with the major groove to achieve that purpose (2pts)? B. Why do the HTH motifs recognize the DNA sequence using the major groove and not the minor groove (2 pts)? Through what kind of interaction between the protein and the DNA minor groove that HTH motifs recognize the correct sequence (2pts)?

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