Question

Three different bacteria species have the following consensus sequences upstream of a conserved gene.

Table 15.2 Order the bacteria from most to least efficient initiation of gene transcription. a. A > B > C b. B > C > A c. C > B > A d. A > C > B

Short answer

Bacterial Species A is the most efficient, followed by Species C, and then Species B. In all three bacterial species, the efficiency of gene transcription initiation is determined by the consensus sequence.

Step-by-step solution

step-1: Introduction

In three bacterial species, the efficiency of gene transcription initiation is determined by their consensus sequence.

step-2: Explanation of correct answers

Option (d) is a good choice. Bacterial Species A is the most efficient, followed by Species C, and then Species B. Bacterial Species A, followed by Species C and Species B, contains the most conserved-10 element. Furthermore, the element of Species A is a conserved consensus sequence, but the elements of Species C and Species B are relatively conserved-35. So, in terms of transcription initiation, bacterial Species A is the most efficient, followed by Species C and Species B.

step-3: Explanation of incorrect answers

Option (a) $A>B>C$is the most common when compared to species C-10 element of TATATT, Bacterial Species A has the most conserved-10 element as TAATAAT, while Bacterial Species B has the least conserved-10 element as TTTAAT. As a result, this ordering option is not appropriate for gene transcription.

Option (b) $B>C>A$. When compared to the other two bacterial species, Bacterial Species B possesses both elements-10 and-35 as TTTAAT and TTGGCC, indicating reduced gene transcription conservation.

Option (c) $C>B>A$. Although the parts of bacterial species C are conserved for gene transcription, the elements of bacterial species A are more conserved than those of species C.