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Kinetic Analysis of S.aureus Biofilm Regulation by Using Combined Imaging and Genome-Wide Approaches

English title Kinetic Analysis of S.aureus Biofilm Regulation by Using Combined Imaging and Genome-Wide Approaches
Applicant Schrenzel Jacques
Number 124717
Funding scheme Project funding (Div. I-III)
Research institution Laboratoire de Recherche Génomique Service des Maladies Infectieuses Hôpital Cantonal - HUG
Institution of higher education University of Geneva - GE
Main discipline Experimental Microbiology
Start/End 01.07.2009 - 31.03.2013
Approved amount 468'000.00
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Keywords (14)

Staphylococcus aureus; biofilms; host-pathogen interactions; chronic infections; foreign-body infections; mRNA messenger profiling; microarrays; gene regulation; transcriptomics; proteomics; genomics; confocal imaging; genetic evolution; high-throughput sequencing

Lay Summary (English)

Lead
Lay summary
S. aureus is a ubiquitous gram-positive bacterium, able to exist on inanimate objects as well as in a variety of niches, such as the skin, mucous membranes, blood, or bones. During its lifetime, a single bacterium can travel from one location to another, exposing the bacteria to multiple environments. These transitions are very likely to require quick switches from a unicellular planktonic lifestyle to settle multicellular communities commonly referred to as biofilms.In this application, we have set the following objectives: (i) further characterize the three mutants (SA0701, codY, and SA1885) using different physiological and biochemical assays, (ii) perform morphological analysis of biofilm development and maturation using confocal light scanning microscopy of fluorescently-labeled S. aureus, (iii) correlate morphologic stages with defined patterns of gene expression, (iv) replicate the 38 mutants by constructing deletion mutants and their complemented isogenic counterparts in the permissive ?hsdR UAMS-1 background, (v) establish a model of dynamic biofilm, (vi) characterize the metabolic conditions of the 38 biofilm-deficient mutants by genome-wide transcription profiling, and (vii) quantify the genetic diversity and study mutations that are selected during biofilm maturation.In summary, molecular and genetic tools developed during previous grant applications will be applied to characterize in details a subset of genes involved in S. aureus biofilm development. We will also address the general question whether biofilm formation represents a developmental program of coordinated gene expression and study the genetic diversification and selection shaping biofilm evolution.
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Publications

Publication
GdpS contributes to Staphylococcus aureus biofilm formation by regulation of eDNA release.
Fischer Adrien, Kambara Kumiko, Meyer Hanna, Stenz Ludwig, Bonetti Eve-Julie, Girard Myriam, Lalk Michael, François Patrice, Schrenzel Jacques (2014), GdpS contributes to Staphylococcus aureus biofilm formation by regulation of eDNA release., in Int. J. Med Microbiol, 304(3-4), 284-299.
A DEAD-box RNA helicase is a key element in persistence and virulence regulation in Staphylococcus aureus
P. REDDER, S. OUN, P. FRANCOIS, A. CORVAGLIA, J.-P. DIDIER, E. BUTTAZZONI, M. GIRARD, J. SCHRENZEL, P. LINDER (2012), A DEAD-box RNA helicase is a key element in persistence and virulence regulation in Staphylococcus aureus, in RNA Biology , année 2012(10), 1-9.
The CodY pleiotropic repressor controls virulence in gram-positive pathogens.
L. STENZ, P. FRANCOIS, P. LINDER, J. SCHRENZEL (2011), The CodY pleiotropic repressor controls virulence in gram-positive pathogens., in FEMS Immunol Med Microbiol., 62(2), 123-139.
The σB-dependent yabJ-spoVG operon is involved in the regulation of extracellular nuclease, lipase, and protease expression in Staphylococcus aureus
Schulthess B, Francois P, Bloes DA, Bischoff M, Schrenzel J, Schrenzel J, M. Girard (2011), The σB-dependent yabJ-spoVG operon is involved in the regulation of extracellular nuclease, lipase, and protease expression in Staphylococcus aureus, in J Bacteriol., 193(18), 4954-4962.

Collaboration

Group / person Country
Types of collaboration
Prof. Urs JENAL, Biozentrum, University of Basel Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Dr. David SCHLEHECK, University of Konstanz Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
Dr Laurent FARINELLI, Fasteris SA, Geneva. Switzerland (Europe)
- Industry/business/other use-inspired collaboration
Prof. Patrick LINDER, University of Geneva Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
Annual Assembly of the Swiss Society for Microbiology Poster GdpS regulates biofilm stability and growth at low temperatures in S. aureus. 21.06.2012 St-Gall, Switzerland Beaume Marie; Girard Myriam; Lazarevic Vladimir; Schrenzel Jacques; Gizard Yann; François Patrice;
4th Congress of European Microbiologists (FEMS) Poster SA0701, the only protein that contains a GGDEF‐motif in S. aureus genome, regulates DNA release in biofilm formation 26.06.2011 Genève, Switzerland François Patrice; Schrenzel Jacques; Lazarevic Vladimir; Girard Myriam;
69th Annual Assembly of the Swiss Society for Microbiology Poster Contribution of cyclic dGMP synthase in Staphylococcus aureus biofilm formation 24.06.2010 Zurich, Switzerland Schrenzel Jacques; Lazarevic Vladimir; François Patrice;


Associated projects

Number Title Start Funding scheme
152873 Kinetic Analysis of S.aureus Biofilm Regulation by Using Combined Imaging and Genome-Wide Approaches 01.05.2014 Project funding (Div. I-III)
112370 Kinetic analysis of S.aureus biofilm regulation by using combined imaging and genome-wide approaches 01.05.2006 Project funding (Div. I-III)

Abstract

S. aureus is a ubiquitous gram-positive bacterium, able to exist on inanimate objects as well as in a variety of niches, such as the skin, mucous membranes, blood, or bones. During its lifetime, a single bacterium can travel from one location to another, exposing the bacteria to multiple environments. These transitions are very likely to require quick switches from a unicellular planktonic lifestyle to settled multicellular communities commonly referred to as biofilms. Unfortunately, S. aureus biofilms resist very efficiently antibiotic treatments, withstand host defense mechanisms, and contribute to persistence in chronic infections. Previous grant applications permitted to identify 38 independent biofilm-deficient S. aureus mutants. Three of them were complemented and are now partly characterized. We also developed and validated a genome-wide S. aureus microarray that allowed linking transcription profiles with quantitative proteomics. We designed a novel software application enabling high-throughput sequencing to address novel fields in bacteriology (de novo sequencing as well as genome-wide SNP detection). We created a series of molecular tools for facilitating genetic manipulations in clinical S. aureus strains (by implementing site-specific integration of the group II intron in S. aureus strains, by constructing hsdR knockout mutants, and by assembling fluorescent reporters for confocal imaging of biofilms). In this application, we have set the following objectives: (i) further characterize the three mutants (SA0701, codY, and SA1885) using different physiological and biochemical assays, (ii) perform morphological analysis of biofilm development and maturation using confocal light scanning microscopy of fluorescently-labeled S. aureus, (iii) correlate morphologic stages with defined patterns of gene expression, (iv) replicate the 38 mutants by constructing deletion mutants and their complemented isogenic counterparts in the permissive ?hsdR UAMS-1 background, (v) establish a model of dynamic biofilm, (vi) characterize the metabolic conditions of the 38 biofilm-deficient mutants by genome-wide transcription profiling, and (vii) quantify the genetic diversity and study mutations that are selected during biofilm maturation. In summary, molecular and genetic tools developed during previous grant applications will be applied to characterize in details a subset of genes involved in S. aureus biofilm development. We will also address the general question whether biofilm formation represents a developmental program of coordinated gene expression and study the genetic diversification and selection shaping biofilm evolution.
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