caption a7 strain relevant characteristics reference  (ATCC)

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: Yersinia and Salmonell a strains used in this study

Article Snippet: No biofilm formation was observed in any of the strains at this temperature ( ). table ft1 table-wrap mode="anchored" t5 TABLE 1 caption a7 Strain Relevant characteristics Reference Y. pestis KIM6+ Molecular grouping 2.MED, pCD1 − 48 Y. pestis KIM6+ Δ phoP KIM6+ phoP Δ127–429 15 Y. pestis KIM6+ phoP-G215 KIM6+ phoP-G215 This work Y. pestis KIM6+ / pGFP KIM6+/p67GFP3.1 Amp r Carb r 49 Salmonella Typhimurium Salmonella enterica serovar Typhimurium ATCC 14028 50 Open in a separate window Yersinia and Salmonell a strains used in this study fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window FIG 2 caption a7 Growth characteristics of Y. pestis strains. (A and B) Y. pestis KIM6+ (wild type [WT]) or the indicated KIM6+-derived strains were cultured overnight in TMH medium containing 20 μM Mg 2+ ( phoP -activating low-Mg 2+ condition) in glass tubes at 21°C (A) or 37°C (B), and their gross growth phenotypes were compared.

Techniques:

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: Growth characteristics of Y. pestis strains. (A and B) Y. pestis KIM6+ (wild type [WT]) or the indicated KIM6+-derived strains were cultured overnight in TMH medium containing 20 μM Mg2+ (phoP-activating low-Mg2+ condition) in glass tubes at 21°C (A) or 37°C (B), and their gross growth phenotypes were compared. The arrows indicate the biofilms formed on the surfaces of the glass tubes. The biofilms appear to have formed above the liquid-air interface, because the liquid was reaching higher levels in the tubes during incubation in a rotary shaker. The pictures are representatives of three independent experiments. (C and D) Growth curve analysis was performed at ambient room temperature (∼23°C) using TMH supplemented with 0.2% ribose as the carbon source. The indicated Y. pestis KIM6+-derived strains were cultured successively over two nights, first in brain heart infusion medium and then in TMH ribose containing 20 mM Mg2+. On day three, the strains were diluted to 1:1,000 in TMH ribose with 20 mM Mg2+ (high Mg2+) (C) or TMH ribose with 10 μM Mg2+ (low Mg2+) (D) and growth was recorded on a Bioscreen C (Growth Curves, USA) for 48 h. Data represent the average from three biological replicates.

Article Snippet: No biofilm formation was observed in any of the strains at this temperature ( ). table ft1 table-wrap mode="anchored" t5 TABLE 1 caption a7 Strain Relevant characteristics Reference Y. pestis KIM6+ Molecular grouping 2.MED, pCD1 − 48 Y. pestis KIM6+ Δ phoP KIM6+ phoP Δ127–429 15 Y. pestis KIM6+ phoP-G215 KIM6+ phoP-G215 This work Y. pestis KIM6+ / pGFP KIM6+/p67GFP3.1 Amp r Carb r 49 Salmonella Typhimurium Salmonella enterica serovar Typhimurium ATCC 14028 50 Open in a separate window Yersinia and Salmonell a strains used in this study fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window FIG 2 caption a7 Growth characteristics of Y. pestis strains. (A and B) Y. pestis KIM6+ (wild type [WT]) or the indicated KIM6+-derived strains were cultured overnight in TMH medium containing 20 μM Mg 2+ ( phoP -activating low-Mg 2+ condition) in glass tubes at 21°C (A) or 37°C (B), and their gross growth phenotypes were compared.

Techniques: Derivative Assay, Cell Culture, Incubation

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: No biofilm formation was observed in any of the strains at this temperature ( ). table ft1 table-wrap mode="anchored" t5 TABLE 1 caption a7 Strain Relevant characteristics Reference Y. pestis KIM6+ Molecular grouping 2.MED, pCD1 − 48 Y. pestis KIM6+ Δ phoP KIM6+ phoP Δ127–429 15 Y. pestis KIM6+ phoP-G215 KIM6+ phoP-G215 This work Y. pestis KIM6+ / pGFP KIM6+/p67GFP3.1 Amp r Carb r 49 Salmonella Typhimurium Salmonella enterica serovar Typhimurium ATCC 14028 50 Open in a separate window Yersinia and Salmonell a strains used in this study fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window FIG 2 caption a7 Growth characteristics of Y. pestis strains. (A and B) Y. pestis KIM6+ (wild type [WT]) or the indicated KIM6+-derived strains were cultured overnight in TMH medium containing 20 μM Mg 2+ ( phoP -activating low-Mg 2+ condition) in glass tubes at 21°C (A) or 37°C (B), and their gross growth phenotypes were compared.

Techniques: Quantitative RT-PCR, Expressing, Comparison, Western Blot, Bacteria, Control, Positive Control

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: Y. pestis phoP G215 mutant strain is more susceptible to antimicrobial peptide polymyxin B a

Article Snippet: No biofilm formation was observed in any of the strains at this temperature ( ). table ft1 table-wrap mode="anchored" t5 TABLE 1 caption a7 Strain Relevant characteristics Reference Y. pestis KIM6+ Molecular grouping 2.MED, pCD1 − 48 Y. pestis KIM6+ Δ phoP KIM6+ phoP Δ127–429 15 Y. pestis KIM6+ phoP-G215 KIM6+ phoP-G215 This work Y. pestis KIM6+ / pGFP KIM6+/p67GFP3.1 Amp r Carb r 49 Salmonella Typhimurium Salmonella enterica serovar Typhimurium ATCC 14028 50 Open in a separate window Yersinia and Salmonell a strains used in this study fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window FIG 2 caption a7 Growth characteristics of Y. pestis strains. (A and B) Y. pestis KIM6+ (wild type [WT]) or the indicated KIM6+-derived strains were cultured overnight in TMH medium containing 20 μM Mg 2+ ( phoP -activating low-Mg 2+ condition) in glass tubes at 21°C (A) or 37°C (B), and their gross growth phenotypes were compared.

Techniques: Mutagenesis

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: KIM6+ ΔphoP mutant is outcompeted by the wild type during flea coinfection, while KIM6+ phoP-G215 can colonize the flea equally well as the wild type. Cohorts of Xenopsylla cheopis fleas were fed on a blood meal containing a 1:1 mixture of wild-type (KIM6+ harboring an ampicillin/carbenicillin resistance cassette on plasmid pGFP [KIM6+/pGFP]) and the indicated phoP mutant or wild-type KIM6+ Y. pestis strains. At days 0 (T0) and 7 (T7) postinfection, Y. pestis cells colonizing the flea midgut were enumerated and the percentages of each strain colonizing the midgut were determined. For each coinfection experiment at a given time point, CFU was determined for 20 to 25 fleas that had fed on infected blood. Data points showing that 0 CFU were recovered from a flea were removed from the analysis (there was no apparent difference among three phoP variant strains in the number of fleas that gave 0 CFU.) Data were plotted as the percentage of the KIM6+/pGFP recovered from each coinfected flea. Error bars represent means ± standard deviations (SDs) from the percentage CFU data. Bars indicate the two groups that were assessed for statistical differences.

Article Snippet: No biofilm formation was observed in any of the strains at this temperature ( ). table ft1 table-wrap mode="anchored" t5 TABLE 1 caption a7 Strain Relevant characteristics Reference Y. pestis KIM6+ Molecular grouping 2.MED, pCD1 − 48 Y. pestis KIM6+ Δ phoP KIM6+ phoP Δ127–429 15 Y. pestis KIM6+ phoP-G215 KIM6+ phoP-G215 This work Y. pestis KIM6+ / pGFP KIM6+/p67GFP3.1 Amp r Carb r 49 Salmonella Typhimurium Salmonella enterica serovar Typhimurium ATCC 14028 50 Open in a separate window Yersinia and Salmonell a strains used in this study fig ft0 fig mode=article f1 fig/graphic|fig/alternatives/graphic mode="anchored" m1 Open in a separate window FIG 2 caption a7 Growth characteristics of Y. pestis strains. (A and B) Y. pestis KIM6+ (wild type [WT]) or the indicated KIM6+-derived strains were cultured overnight in TMH medium containing 20 μM Mg 2+ ( phoP -activating low-Mg 2+ condition) in glass tubes at 21°C (A) or 37°C (B), and their gross growth phenotypes were compared.

Techniques: Mutagenesis, Plasmid Preparation, Infection, Variant Assay