File:GE23077-binds-to-the-RNA-polymerase-i-and-i+1-sites-and-prevents-the-binding-of-initiating-elife02450f006.jpg

English: (A) Partial-competitive binding of GE and Rif: association kinetics for Rif in presence of 0–2000 nM GE. (B) Partial-competitive binding of GE and Rif: association kinetics for Rif in presence of 2000 nM GE, using wild-type RNAP (red) and GE-resistant RNAP derivatives [Asp565]β-RNAP (black) and [Lys684]β-RNAP (blue). (C) Partial-competitive binding of GE and Rif: kon, koff, and Kd for Rif in absence of GE and in presence of saturating GE (160 nM or 2000 nM; ∼30 × Ki or ∼300 × Ki). (D) Superimposition of crystal structures of RPo-GE and RNAP-Rif: inferred simultaneous binding. Blue mesh, blue sticks, gray ribbon, and violet sphere: mFo-DFc omit map for GE, atomic model for GE, RNAP, and Mg2+(I) from RPo-GE (Figure 4). Yellow sticks: Rif from RNAP-Rif (PDB: 1YNN). Green surfaces, GE target residues at which substitutions confer GE-resistance; red surfaces, residues at which substitutions confer Rif-resistance. (E) Crystal structure of RPo-GE plus Rif: crystallographic data and refinement statistics. (F) Crystal structure of RPo-GE plus Rif: electron density and model. Yellow mesh, patchy electron density potentially attributable to Rif (mFo-DFc omit map; contoured at 2.7σ). Other colors as in D. (G) Crystal structure of RPo-GE-RifSV: crystallographic data and refinement statistics. (H) Crystal structure of RPo-GE-RifSV: electron density and model. Yellow mesh, mFo-Fc omit map for RifSV (contoured at 2.7σ); yellow sticks, RifSV. Other colors as in D. See Figure 6—figure supplements 1, 2.