Staphylococcus epidermidis SrrAB Regulates Bacterial Growth and Biofilm Formation Differently under Oxic and Microaerobic Conditions

Wu, Youcong; Wu, Yang; Zhu, Tao; Han, Haiyan; Liu, Huayong; Xu, Tao; François, Patrice; Fischer, Adrien; Bai, Li; Götz, Friedrich; Qu, Di

doi:10.1128/jb.02231-14

Cited by 40 publications

(35 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Biofilm formation is influenced by environmental factors, including multiple species interactions (Lee et al ., ), as well as transcriptional variation (Wu et al ., ) and phase variation (Brooks and Jefferson, ). However, differences in the genes associated with biofilm formation within species are less well characterized.…”

Section: Discussionmentioning

confidence: 99%

Enhanced biofilm formation and multi‐host transmission evolve from divergent genetic backgrounds in Campylobacter jejuni

Pascoe

Méric

Murray

et al. 2015

Environmental Microbiology

View full text Add to dashboard Cite

SummaryMulticellular biofilms are an ancient bacterial adaptation that offers a protective environment for survival in hostile habitats. In microaerophilic organisms such as C ampylobacter, biofilms play a key role in transmission to humans as the bacteria are exposed to atmospheric oxygen concentrations when leaving the reservoir host gut. Genetic determinants of biofilm formation differ between species, but little is known about how strains of the same species achieve the biofilm phenotype with different genetic backgrounds. Our approach combines genome‐wide association studies with traditional microbiology techniques to investigate the genetic basis of biofilm formation in 102 C ampylobacter jejuni isolates. We quantified biofilm formation among the isolates and identified hotspots of genetic variation in homologous sequences that correspond to variation in biofilm phenotypes. Thirteen genes demonstrated a statistically robust association including those involved in adhesion, motility, glycosylation, capsule production and oxidative stress. The genes associated with biofilm formation were different in the host generalist ST‐21 and ST‐45 clonal complexes, which are frequently isolated from multiple host species and clinical samples. This suggests the evolution of enhanced biofilm from different genetic backgrounds and a possible role in colonization of multiple hosts and transmission to humans.

show abstract

Section: Discussionmentioning

confidence: 99%

Enhanced biofilm formation and multi‐host transmission evolve from divergent genetic backgrounds in Campylobacter jejuni

Pascoe

Méric

Murray

et al. 2015

Environmental Microbiology

View full text Add to dashboard Cite

show abstract

“…These data suggest that the ⌬srrAB mutant is necessary for anaerobic growth but conversely may be detrimental to survival within an anaerobic environment. It has been suggested that the decreased expression of genes involved in anaerobic metabolism may be responsible for the altered growth and survival of the ⌬srrAB mutant under these conditions (16). For example, the discrepancy between growth and survival may be explained by the dysregulation of the nrdDG and nar operons (17).…”

Section: Discussionmentioning

confidence: 99%

“…Previous studies have demonstrated a pronounced cell death phenotype associated with the ⌬srrAB mutation (16,17). Given that transcription profiling experiments suggested that the SrrAB regulatory system has a negative effect on cidABC transcription (17) and that medium acidification due to the accumulation of acidic fermentative metabolites can influence cell fate (13), we initially tested the hypothesis that increased cidC-dependent acetate production was responsible for the decreased survival of an S. aureus ⌬srrAB mutant relative to that of the wild-type strain.…”

Section: Disruption Of Srrab Enhances Weak Acid-dependent Deathmentioning

confidence: 99%

“…Recent studies have also demonstrated that cidABC expression is influenced by the SrrAB two-component system, which is known to be important for anaerobic growth and survival (15). Disruption of srrAB resulted in enhanced cell death and decreased biofilm thickness (16,17), likely as a result of the role that this regulatory system has in adaptation to an anaerobic environment. In the current study, we demonstrated that the increased death exhibited by the ⌬srrAB mutant is a function of increased cidABC expression caused by the ⌬srrAB mutation.…”

mentioning

confidence: 99%

See 1 more Smart Citation

SrrAB Modulates Staphylococcus aureus Cell Death through Regulation of cidABC Transcription

et al. 2016

View full text Add to dashboard Cite

The death and lysis of a subpopulation in Staphylococcus aureus biofilm cells are thought to benefit the surviving population by releasing extracellular DNA, a critical component of the biofilm extracellular matrix. Although the means by which S. aureus controls cell death and lysis is not understood, studies implicate the role of the cidABC and lrgAB operons in this process. Recently, disruption of the srrAB regulatory locus was found to cause increased cell death during biofilm development, likely as a result of the sensitivity of this mutant to hypoxic growth. In the current study, we extended these findings by demonstrating that cell death in the ⌬srrAB mutant is dependent on expression of the cidABC operon. The effect of cidABC expression resulted in the generation of increased reactive oxygen species (ROS) accumulation and was independent of acetate production. Interestingly, consistently with previous studies, cidC-encoded pyruvate oxidase was found to be important for the generation of acetic acid, which initiates the cell death process. However, these studies also revealed for the first time an important role of the cidB gene in cell death, as disruption of cidB in the ⌬srrAB mutant background decreased ROS generation and cell death in a cidCindependent manner. The cidB mutation also caused decreased sensitivity to hydrogen peroxide, which suggests a complex role for this system in ROS metabolism. Overall, the results of this study provide further insight into the function of the cidABC operon in cell death and reveal its contribution to the oxidative stress response. IMPORTANCEThe manuscript focuses on cell death mechanisms in Staphylococcus aureus and provides important new insights into the genes involved in this ill-defined process. By exploring the cause of increased stationary-phase death in an S. aureus ⌬srrAB regulatory mutant, we found that the decreased viability of this mutant was a consequence of the overexpression of the cidABC operon, previously shown to be a key mediator of cell death. These investigations highlight the role of the cidB gene in the death process and the accumulation of reactive oxygen species. Overall, the results of this study are the first to demonstrate a positive role for CidB in cell death and to provide an important paradigm for understanding this process in all bacteria.

show abstract

“…Detection of PIA and extracellular DNA Detection of PIA and eDNA from static biofilms was performed as previously described with a few modifications (Mann et al 2009;Wu et al 2015). Briefly, the dishes were chilled at 4°C for 15 min and 10 ll of 0.5 M EDTA was added.…”

Section: Static Biofilm Assaysmentioning

confidence: 99%

Effect of negative pressure on growth, secretion and biofilm formation of Staphylococcus aureus

Wang

Yin

et al. 2015

Antonie van Leeuwenhoek

View full text Add to dashboard Cite

Negative pressure wound therapy (NPWT) has gained popularity in the management of contaminated wounds as an effective physical therapy, although its influence on the bacteria in the wounds remains unclear. In this study, we attempted to explore the effect of negative pressure conditions on Staphylococcus aureus, the most frequently isolated pathogen during wound infection. S. aureus was cultured in Luria-Bertani medium at subatmospheric pressure of -125 mmHg for 24 h, with the bacteria grown at ambient pressure as the control. The application of negative pressure was found to slow down the growth rate and inhibit biofilm development of S. aureus, which was confirmed by static biofilm assays. Furthermore, decreases in the total amount of virulence factors and biofilm components were observed, including α-hemolysin, extracellular adherence protein, polysaccharide intercellular adhesin and extracellular DNA. With quantitative RT-PCR analysis, we also revealed a significant inhibition in the transcription of virulence and regulatory genes related to wound infections and bacterial biofilms. Together, these findings indicated that negative pressure could inhibit the growth, virulence and biofilm formation of S. aureus. A topical subatmospheric pressure condition, such as NPWT, may be a potential antivirulence and antibiofilm strategy in the field of wound care.

show abstract

Staphylococcus epidermidis SrrAB Regulates Bacterial Growth and Biofilm Formation Differently under Oxic and Microaerobic Conditions

Cited by 40 publications

References 45 publications

Enhanced biofilm formation and multi‐host transmission evolve from divergent genetic backgrounds in Campylobacter jejuni

Enhanced biofilm formation and multi‐host transmission evolve from divergent genetic backgrounds in Campylobacter jejuni

SrrAB Modulates Staphylococcus aureus Cell Death through Regulation of cidABC Transcription

Effect of negative pressure on growth, secretion and biofilm formation of Staphylococcus aureus

Contact Info

Product

Resources

About