ygsIs a Novel Gene That Influences Biofilm Formation and the General Stress Response ofStaphylococcus epidermidis

ABSTRACTInfections caused by the nosocomial pathogenStaphylococcus epidermidisfrequently develop on implanted medical devices and involve biofilm formation. Biofilms are surface-attached microbial communities that show increased resistance to drug treatment and mechanisms of innate host defense. In this study, a mutant library of the clinical isolateS. epidermidis1457 was constructed using mariner-based transposon mutagenesis. About a thousand mutants were screened, and 12 mutants were identified as significantly defective in biofilm formation. We focused on a mutant in which the transposon had inserted in a gene with unknown function,SERP0541, which is annotated as a gene encoding a GSP13-like general stress response protein. The gene was namedygs(encoding an unknowngeneralstress protein). Various stresses, including heat, pH, high osmolarity, and ethanol affected the survival of theygsmutant to a significantly higher degree than the wild-type strain and led to increased expression ofygs. Furthermore, synthesis of polysaccharide intercellular adhesin (PIA) and transcription of the PIA biosynthetic operon were significantly decreased in theygsmutant. These results are in accordance with the putative involvement ofygsin stress-response gene regulation and indicate thatygsinfluences biofilm development by controlling PIA-dependent biofilm accumulation. Moreover,ygshad a significant impact on the formation of biofilms and metastatic disease in two catheter-related rat infection models. Our study shows that theygsgene controlsS. epidermidisbiofilm accumulation and stress resistance, representing a key regulator of both structural and physiological biofilm characteristics with a significant impact on biofilm-associated infection.

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THE ROLE OF GENERAL STRESS RESPONSE REGULATOR RpoS IN BIOFILM FORMATION BY ESCHERICHIA COLI IN THE PRESENCE OF PLANT POLYPHENOLS

Book of proceedings of the All-Russian Scientific Conference with International Participation and Schools of Young Scientists "Mechanisms of resistance of plants and microorganisms to unfavorable environmental" (parts I, II) ◽

10.31255/978-5-94797-319-8-703-705 ◽

2018 ◽

Author(s):

Z.Y. Samoylova ◽

G.V. Smirnova ◽

O.N. Oktyabrsky

Keyword(s):

Escherichia Coli ◽

Stress Response ◽

Biofilm Formation ◽

Response Regulator ◽

Plant Polyphenols ◽

General Stress Response ◽

General Stress

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Ensifer aridi LMR001T Symbiosis and Tolerance to Stress Do Not Require the Alternative Sigma Factor RpoE2

Agronomy ◽

10.3390/agronomy11091787 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1787

Author(s):

Meryem Belfquih ◽

Ilham Sakrouhi ◽

Hassan Ait-Benhassou ◽

Emeric Dubois ◽

Dany Severac ◽

...

Keyword(s):

Stress Response ◽

Sigma Factor ◽

A Priori ◽

Climatic Conditions ◽

Targeted Mutagenesis ◽

Alternative Sigma Factor ◽

Gene Encoding ◽

General Stress Response ◽

Stress Genes ◽

General Stress

The recently proposed species Ensifer aridi represents an interesting model to study adaptive mechanisms explaining its maintenance under stressful pedo-climatic conditions. To get insights into functions associated with hyperosmotic stress adaptation in E. aridi, we first performed RNAseq profiling of cells grown under sub-lethal stresses applied by permeating (NaCl) and non-permeating (PEG8000) solutes that were compared to a transcriptome from unstressed bacteria. Then an a priori approach, consisting of targeted mutagenesis of the gene encoding alternative sigma factor (rpoE2), involved in the General Stress Response combined with phenotyping and promoter gfp fusion-based reporter assays of selected genes was carried out to examine the involvement of rpoE2 in symbiosis and stress response. The majority of motility and chemotaxis genes were repressed by both stresses. Results also suggest accumulation of compatible solute trehalose under stress and other metabolisms such as inositol catabolism or the methionine cycling-generating S-adenosyl methionine appears strongly induced notably under salt stress. Interestingly, many functions regulated by salt were shown to favor competitiveness for nodulation in other rhizobia, supporting a role of stress genes for proper symbiosis’ development and functioning. However, despite activation of the general stress response and identification of several genes possibly under its control, our data suggest that rpoE2 was not essential for stress tolerance and symbiosis’ development, indicating that E. aridi possesses alternative regulatory mechanisms to adapt and respond to stressful environments.

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Genome-Wide Identification of H-NS-Controlled, Temperature-Regulated Genes in Escherichiacoli K-12

Journal of Bacteriology ◽

10.1128/jb.00599-08 ◽

2008 ◽

Vol 191 (3) ◽

pp. 1106-1110 ◽

Cited By ~ 46

Author(s):

Christine A. White-Ziegler ◽

Talya R. Davis

Keyword(s):

Stress Response ◽

Biofilm Formation ◽

Dna Microarrays ◽

Cold Shock ◽

Nutrient Acquisition ◽

General Stress Response ◽

General Stress ◽

Genome Wide ◽

K 12 ◽

Common Regulator

ABSTRACT DNA microarrays demonstrate that H-NS controls 69% of the temperature regulated genes in Escherichia coli K-12. H-NS is shown to be a common regulator of multiple iron and other nutrient acquisition systems preferentially expressed at 37°C and of general stress response, biofilm formation, and cold shock genes highly expressed at 23°C.

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