#Question id: 4453
#Unit 3. Fundamental Processes
Correct statements about regions of the s70 factor which can be divided into four regions called s region 1 through s region 4;
#Question id: 4454
#Unit 3. Fundamental Processes
Correct series of sigma regions,
#Question id: 4455
#Unit 3. Fundamental Processes
The __I is connected to the II by a flexible linker, although the II is embedded in the body of the enzyme, the I can reach the upstream element and can do so even when that element is not located immediately adjacent to the –35 region, but further upstream.
#Question id: 4456
#Unit 3. Fundamental Processes
Correct statement about two striking structural changes are seen in the enzyme upon isomerization from the closed to the open complex;
A. First, the pincers at the front of the enzyme clamp down tightly on the downstream DNA.
B. Second, there is a major shift in the position of the amino-terminal region of s. When not bound to DNA, s region 3.2 lies within the active center cleft of the holoenzyme, blocking the path that, in the open complex, is followed by the template DNA strand.
C. In the open complex, region 1.1 shifts some 50 A˚ and is now found on the outside of the enzyme, allowing the DNA access to the cleft.
D. Region 1.1 of s is highly negatively charged ( just like DNA).
#Question id: 4457
#Unit 3. Fundamental Processes
In the holoenzyme, which sigma region acts as a molecular mimic of DNA?
#Question id: 4458
#Unit 3. Fundamental Processes
What structural changes will occur at the time of transition to the open complex and how we describe this transition in transcription,