Extracellular DNA Is Essential for Maintaining Bordetella Biofilm Integrity on Abiotic Surfaces and in the Upper Respiratory Tract of Mice

Conover, Matt S.; Mishra, Meenu; Deora, Rajendar

doi:10.1371/journal.pone.0016861

Cited by 103 publications

(76 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We have shown that both B. bronchiseptica and B. pertussis are capable of forming biofilms in the upper respiratory tract of infected animals (13,14,53). These findings, combined with the presence of clusters, microcolonies, and tangles of B. bronchiseptica and B. pertussis bacteria in explant tissues and nasal biopsy specimens of patients, strengthen the hypothesis that Bordetella bacteria utilize biofilms as a means to persist and circulate between their mammalian hosts (22,47,54).…”

supporting

confidence: 65%

BpsR Modulates Bordetella Biofilm Formation by Negatively Regulating the Expression of the Bps Polysaccharide

et al. 2012

Self Cite

View full text Add to dashboard Cite

Bordetella bacteria are Gram-negative respiratory pathogens of animals, birds, and humans. A hallmark feature of some Bordetella species is their ability to efficiently survive in the respiratory tract even after vaccination. Bordetella bronchiseptica and Bordetella pertussis form biofilms on abiotic surfaces and in the mouse respiratory tract. The Bps exopolysaccharide is one of the critical determinants for biofilm formation and the survival of Bordetella in the murine respiratory tract. In order to gain a better understanding of regulation of biofilm formation, we sought to study the mechanism by which Bps expression is controlled in Bordetella. Expression of bpsABCD (bpsA-D) is elevated in biofilms compared with levels in planktonically grown cells. We found that bpsA-D is expressed independently of BvgAS. Subsequently, we identified an open reading frame (ORF), BB1771 (designated here bpsR), that is located upstream of and in the opposite orientation to the bpsA-D locus. BpsR is homologous to the MarR family of transcriptional regulators. Measurement of bpsA and bpsD transcripts and the Bps polysaccharide levels from the wild-type and the ⌬bpsR strains suggested that BpsR functions as a repressor. Consistent with enhanced production of Bps, the bpsR mutant displayed considerably more structured biofilms. We mapped the bpsA-D promoter region and showed that purified BpsR protein specifically bound to the bpsA-D promoter. Our results provide mechanistic insights into the regulatory strategy employed by Bordetella for control of the production of the Bps polysaccharide and biofilm formation.

show abstract

supporting

confidence: 65%

BpsR Modulates Bordetella Biofilm Formation by Negatively Regulating the Expression of the Bps Polysaccharide

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…B. pertussis strains were maintained on Bordet-Gengou agar (BG) supplemented with 10% defibrinated sheep blood. Liquid cultures were grown in Stainer-Scholte (SS) broth with heptakis (2,6-di-O-methyl-␤-cyclodextrin) (21,22). Escherichia coli strains were grown in Luria-Bertani medium.…”

Section: Methodsmentioning

confidence: 99%

d -Alanine Modification of a Protease-Susceptible Outer Membrane Component by the Bordetella pertussis dra Locus Promotes Resistance to Antimicrobial Peptides and Polymorphonuclear Leukocyte-Mediated Killing

et al. 2013

Self Cite

View full text Add to dashboard Cite

bBordetella pertussis is the causative agent of pertussis, a highly contagious disease of the human respiratory tract. Despite very high vaccine coverage, pertussis has reemerged as a serious threat in the United States and many developing countries. Thus, it is important to pursue research to discover unknown pathogenic mechanisms of B. pertussis. We have investigated a previously uncharacterized locus in B. pertussis, the dra locus, which is homologous to the dlt operons of Grampositive bacteria. The absence of the dra locus resulted in increased sensitivity to the killing action of antimicrobial peptides (AMPs) and human phagocytes. Compared to the wild-type cells, the mutant cells bound higher levels of cationic proteins and peptides, suggesting that dra contributes to AMP resistance by decreasing the electronegativity of the cell surface. The presence of dra led to the incorporation of D-alanine into an outer membrane component that is susceptible to proteinase K cleavage. We conclude that dra encodes a virulence-associated determinant and contributes to the immune resistance of B. pertussis. With these findings, we have identified a new mechanism of surface modification in B. pertussis which may also be relevant in other Gram-negative pathogens.

show abstract

“…If extracellular DNA is a major structural component of the biofilm matrix, as seen for other bacterial biofilms (365), it could serve as a target for treatment with DNase I. DNase I has been reported to disrupt biofilms (65). D-Amino acids have been reported to prevent biofilm formation (177).…”

Section: Molecular Mechanisms Involved In Pathogenesis Biofilmsmentioning

confidence: 99%

Stenotrophomonas maltophilia: an Emerging Global Opportunistic Pathogen

2012

View full text Add to dashboard Cite

SUMMARY Stenotrophomonas maltophilia is an emerging multidrug-resistant global opportunistic pathogen. The increasing incidence of nosocomial and community-acquired S. maltophilia infections is of particular concern for immunocompromised individuals, as this bacterial pathogen is associated with a significant fatality/case ratio. S. maltophilia is an environmental bacterium found in aqueous habitats, including plant rhizospheres, animals, foods, and water sources. Infections of S. maltophilia can occur in a range of organs and tissues; the organism is commonly found in respiratory tract infections. This review summarizes the current literature and presents S. maltophilia as an organism with various molecular mechanisms used for colonization and infection. S. maltophilia can be recovered from polymicrobial infections, most notably from the respiratory tract of cystic fibrosis patients, as a cocolonizer with Pseudomonas aeruginosa . Recent evidence of cell-cell communication between these pathogens has implications for the development of novel pharmacological therapies. Animal models of S. maltophilia infection have provided useful information about the type of host immune response induced by this opportunistic pathogen. Current and emerging treatments for patients infected with S. maltophilia are discussed.

show abstract

Extracellular DNA Is Essential for Maintaining Bordetella Biofilm Integrity on Abiotic Surfaces and in the Upper Respiratory Tract of Mice

Cited by 103 publications

References 55 publications

BpsR Modulates Bordetella Biofilm Formation by Negatively Regulating the Expression of the Bps Polysaccharide

BpsR Modulates Bordetella Biofilm Formation by Negatively Regulating the Expression of the Bps Polysaccharide

d -Alanine Modification of a Protease-Susceptible Outer Membrane Component by the Bordetella pertussis dra Locus Promotes Resistance to Antimicrobial Peptides and Polymorphonuclear Leukocyte-Mediated Killing

Stenotrophomonas maltophilia: an Emerging Global Opportunistic Pathogen

Contact Info

Product

Resources

About