Journal: Journal of Bacteriology
Article Title: A Single Amino Acid Change in the Response Regulator PhoP, Acquired during Yersinia pestis Evolution, Affects PhoP Target Gene Transcription and Polymyxin B Susceptibility
doi: 10.1128/JB.00050-18
Figure Lengend Snippet: ugd transcript levels are decreased in Y. pestis KIM6+ phoP-G215, while phoP transcript or PhoP protein levels are unaffected. (A to C) mRNA levels of the PhoP-regulated gene ugd at 21°C (A) and 37°C (B), as well as phoP at 21°C (C), were determined in the indicated Y. pestis strains by RT-qPCR. The strains were grown overnight (o/n) at indicated temperatures in low-Mg2+ (20 μM MgCl2) TMH medium. The results were normalized against the 16S rRNA expression levels. Relative levels of expression (with the wild-type levels set at 1) are shown. Data represent the averages from at least three biological replicates. Error bars represent standard errors of the means (SEMs). The asterisks indicate significant differences compared to KIM6+ WT (*, P < 0.05; ***, P < 0.001) and “n.s.” denotes not significant statistically (P > 0.05) as determined by one-way ANOVA with Tukey's multiple-comparison tests. (D) PhoP protein levels of the indicated strains were compared by immunoblotting. Approximately 2 × 108 bacteria grown in low-Mg2+ TMH medium were lysed in 1× Laemmli sample buffer and loaded in each lane. DnaK protein levels were used as a loading control, and Salmonella Typhimurium was used as a positive control for the anti-PhoP antibody. At least three independent experiments were performed and the images of a representative blot are shown.
Article Snippet: When appropriate, statistical tests were performed using a one-way analysis of variance (ANOVA) with Tukey's multiple-comparison test (Prism version 4.0c for Macintosh; GraphPad Software, San Diego, CA).
Techniques: Quantitative RT-PCR, Expressing, Western Blot, Positive Control