The Core and Holoenzyme Forms of RNA Polymerase from <i>Mycobacterium smegmatis</i>.

ABSTRACT: Bacterial RNA polymerase (RNAP) is essential for gene expression and as such is a valid drug target. Hence, it is imperative to know its structure and dynamics. Here, we present two as-yet-unreported forms of Mycobacterium smegmatis RNAP: core and holoenzyme containing σ^A but no other factors. Each form was detected by cryo-electron microscopy in two major conformations. Comparisons of these structures with known structures of other RNAPs reveal a high degree of conformational flexibility of the mycobacterial enzyme and confirm that region 1.1 of σ^A is directed into the primary channel of RNAP. Taken together, we describe the conformational changes of unrestrained mycobacterial RNAP.IMPORTANCE We describe here three-dimensional structures of core and hol

SUBMITTER: Kouba T 

PROVIDER: S-EPMC6351736 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature