Which statement is TRUE regarding E. coli RNAP? A) The dissociation constant (K_d) for promoter DNA and the core enzyme is smaller than that for promoter DNA and the associated holoenzyme. B) The dissociation constant (K_d) for non-promoter sequences and the RNAP holoenzyme is larger than the K_d for the core enzyme and nonpromoter DNA. C) The dissociation constant (K_d) for promoter sequences and the RNAP holoenzyme is the same as the K_d for the core enzyme and nonpromoter DNA. D) All of the statements are true. E) None of the statements is true.

Question

Quizplus · Accepted Answer

The statement that is true regarding E. coli RNAP is B, which states that the dissociation constant for non-promoter sequences and the RNAP holoenzyme is larger than the K_d for the core enzyme and non-promoter DNA. This is because the RNAP holoenzyme has additional subunits that can interact with non-promoter sequences, leading to a weaker binding affinity compared to the core enzyme. Statements A and C are incorrect as they provide incorrect information regarding the dissociation constant for promoter DNA and non-promoter DNA with either the core enzyme or holoenzyme. Statement D is incorrect as only statement B is true. Therefore, the correct answer is B.

Which Statement Is TRUE Regarding E. Coli RNAP