1l9u

From Proteopedia

Revision as of 18:17, 20 November 2007

THERMUS AQUATICUS RNA POLYMERASE HOLOENZYME AT 4 A RESOLUTION

Overview

The crystal structure of the initiating form of Thermus aquaticus RNA, polymerase, containing core RNA polymerase (alpha2betabeta'omega) and the, promoter specificity sigma subunit, has been determined at 4 angstrom, resolution. Important structural features of the RNA polymerase and their, roles in positioning sigma within the initiation complex are delineated, as well as the role played by sigma in modulating the opening of the RNA, polymerase active-site channel. The two carboxyl-terminal domains of sigma, are separated by 45 angstroms on the surface of the RNA polymerase, but, are linked by an extended loop. The loop winds near the RNA polymerase, active site, where it may play a role in initiating nucleotide substrate, binding, and out through the RNA exit channel. The advancing RNA, transcript must displace the loop, leading to abortive initiation and, ultimately to sigma release.

About this Structure

1L9U is a Protein complex structure of sequences from Thermus aquaticus with MG and ZN as ligands. Active as DNA-directed RNA polymerase, with EC number 2.7.7.6 Full crystallographic information is available from OCA.

Reference

Structural basis of transcription initiation: RNA polymerase holoenzyme at 4 A resolution., Murakami KS, Masuda S, Darst SA, Science. 2002 May 17;296(5571):1280-4. PMID:12016306

Page seeded by OCA on Tue Nov 20 20:24:46 2007