Faculty Opinions recommendation of Modulation of Pseudomonas aeruginosa gene expression by host microflora through interspecies communication.

ABSTRACT Airway epithelium is the initial point of host-pathogen interaction in Pseudomonas aeruginosa infection, an important pathogen in cystic fibrosis and nosocomial pneumonia. We used global gene expression analysis to determine airway epithelial transcriptional responses dependent on matrilysin (matrix metalloproteinase 7 [MMP-7]) and stromelysin-2 (MMP-10), two MMPs induced by acute P. aeruginosa pulmonary infection. Extraction of differential gene expression (EDGE) analysis of gene expression changes in P. aeruginosa-infected organotypic tracheal epithelial cell cultures from wild-type, Mmp7 −/−, and Mmp10 −/− mice identified 2,091 matrilysin-dependent and 1,628 stromelysin-2-dependent genes that were differentially expressed. Key node network analysis showed that these MMPs controlled distinct gene expression programs involved in proliferation, cell death, immune responses, and signal transduction, among other host defense processes. Our results demonstrate discrete roles for these MMPs in regulating epithelial responses to Pseudomonas infection and show that a global genomics strategy can be used to assess MMP function.

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Pseudomonas aeruginosa PA14 biofilms produce R-bodies, extendable protein polymers with roles in host colonization and virulence

10.1101/2020.10.26.356394 ◽

2020 ◽

Author(s):

Bryan Wang ◽

Yu-Cheng Lin ◽

Jeanyoung Jo ◽

Alexa Price-Whelan ◽

Shujuan Tao McDonald ◽

...

Keyword(s):

Gene Expression ◽

Pseudomonas Aeruginosa ◽

Host Colonization ◽

Biofilm Growth ◽

Protein Polymers ◽

Virulent Strains

reb genes code for R-bodies: large, extendable polymers that are known for their roles in obligate endosymbioses. In the non-endosymbiotic pathogen Pseudomonas aeruginosa, reb homologues are part of a cluster found in virulent strains. Here, we demonstrate that R-bodies are produced in abundance by P. aeruginosa PA14 subpopulations during biofilm growth, identify regulators of reb gene expression, and show that reb genes are required for full colonization and virulence in host models.

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Local and Global Regulators Linking Anaerobiosis to cupA Fimbrial Gene Expression in Pseudomonas aeruginosa

Journal of Bacteriology ◽

10.1128/jb.01344-07 ◽

2007 ◽

Vol 189 (23) ◽

pp. 8667-8676 ◽

Cited By ~ 29

Author(s):

Isabelle Vallet-Gely ◽

Josh S. Sharp ◽

Simon L. Dove

Keyword(s):

Gene Expression ◽

Pseudomonas Aeruginosa ◽

Opportunistic Pathogen ◽

Phase Variable ◽

Global Regulators ◽

Variable Expression ◽

Regulatory Cascade ◽

Abiotic Surfaces ◽

Positive Regulators ◽

Anaerobic Environment

ABSTRACT The cupA gene cluster of Pseudomonas aeruginosa encodes components and assembly factors of a putative fimbrial structure that enable this opportunistic pathogen to form biofilms on abiotic surfaces. In P. aeruginosa the control of cupA gene expression is complex, with the H-NS-like MvaT protein functioning to repress phase-variable (on/off) expression of the operon. Here we identify four positive regulators of cupA gene expression, including three unusual regulators encoded by the cgrABC genes and Anr, a global regulator of anaerobic gene expression. We show that the cupA genes are expressed in a phase-variable manner under anaerobic conditions and that the cgr genes are essential for this expression. We show further that cgr gene expression is negatively controlled by MvaT and positively controlled by Anr and anaerobiosis. Expression of the cupA genes therefore appears to involve a regulatory cascade in which anaerobiosis, signaled through Anr, stimulates expression of the cgr genes, resulting in a concomitant increase in cupA gene expression. Our findings thus provide mechanistic insight into the regulation of cupA gene expression and identify anaerobiosis as an inducer of phase-variable cupA gene expression, raising the possibility that phase-variable expression of fimbrial genes important for biofilm formation may occur in P. aeruginosa persisting in the largely anaerobic environment of the cystic fibrosis host lung.

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Cross-Species GacA-Controlled Induction of Antibiosis in Pseudomonads

Applied and Environmental Microbiology ◽

10.1128/aem.01681-06 ◽

2006 ◽

Vol 73 (2) ◽

pp. 650-654 ◽

Cited By ~ 35

Author(s):

Christophe Dubuis ◽

Dieter Haas

Keyword(s):

Pseudomonas Aeruginosa ◽

Pseudomonas Fluorescens ◽

Small Rnas ◽

Homoserine Lactone ◽

Signal Molecules ◽

Acyl Homoserine Lactone ◽

Pseudomonas Corrugata ◽

Interspecies Communication ◽

Antibiotic Compounds ◽

Culture Supernatants

ABSTRACT Signal extracts prepared from culture supernatants of Pseudomonas fluorescens CHA0 and Pseudomonas aeruginosa PAO stimulated GacA-dependent expression of small RNAs and hence of antibiotic compounds in both hosts. Pseudomonas corrugata LMG2172 and P. fluorescens SBW25 also produced signal molecules stimulating GacA-controlled antibiotic synthesis in strain CHA0, illustrating a novel, N-acyl-homoserine lactone-independent type of interspecies communication.

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