Fig. 1: An unbiased genetic selection strategy identifies KrrA as a regulatory factor in HitRS signaling.
From: An RNA-binding protein acts as a major post-transcriptional modulator in Bacillus anthracis
A Schematic of the genetic selection strategy: a strain containing ermC driven by a HitR promoter (PhitermC) was plated on medium containing toxic levels of erythromycin and colonies that arose represented bacteria that acquired mutations that constitutively activate the Phit promoter. B All 21 erythromycin-resistant suppressors isolated from genetic selections exhibit frameshift mutations at five different positions within krrA. C, D Growth kinetics of B. anthracis WT, WT PhitermC, ΔkrrA PhitermC, ΔkrrA ΔhitRS PhitermC, and the complemented strain ΔkrrA PhitermC pOS1.PlgtkrrA-3xFLAG in vehicle (C) or 20 µg ml-1 erythromycin (D) were monitored for 24 h. The experiments were conducted at least three times. Data shown are averages of three biological replicates (mean ± SD).
