Logo image
Back
Characterization of biofilm matrix, degradation by DNase treatment and evidence of capsule downregulation in Streptococcus pneumoniae clinical isolates
Journal article   Open access   Peer reviewed

Characterization of biofilm matrix, degradation by DNase treatment and evidence of capsule downregulation in Streptococcus pneumoniae clinical isolates

Luanne Hall-Stoodley, Laura Nistico, Karthik Sambanthamoorthy, Bethany Dice, Duc Nguyen, William J Mershon, Candice Johnson, Fen Ze Hu, Paul Stoodley, Garth D Ehrlich, …
BMC microbiology, v 8(1), pp 173-173
08 Oct 2008
DOI: https://doi.org/10.1186/1471-2180-8-173
PMID: 18842140
Featured in Collection :   UN Sustainable Development Goals @ Drexel
url
https://doi.org/10.1186/1471-2180-8-173View
Published, Version of Record (VoR) Open

Abstract

Biofilms - drug effects DNA, Bacterial - isolation & purification DNA, Bacterial - metabolism Humans Bacterial Proteins - genetics Biofilms - growth & development Gene Expression Profiling Colony Count, Microbial Azithromycin - pharmacology Deoxyribonuclease I - metabolism Streptococcus pneumoniae - isolation & purification Anti-Bacterial Agents - pharmacology Bacterial Proteins - biosynthesis Nasopharynx - microbiology Child Streptococcus pneumoniae - physiology
Streptococcus pneumoniae is a common respiratory pathogen and a major causative agent of respiratory infections, including otitis media (OM). Pneumococcal biofilms have been demonstrated on biopsies of the middle ear mucosa in children receiving tympanostomy tubes, supporting the hypothesis that chronic OM may involve biofilm development by pathogenic bacteria as part of the infectious process. To better understand pneumococcal biofilm formation six low-passage encapsulated nasopharyngeal isolates of S. pneumoniae were assessed over a six-eight day period in vitro. Multiparametric analysis divided the strains into two groups. Those with a high biofilm forming index (BFI) were structurally complex, exhibited greater lectin colocalization and were more resistant to azithromycin. Those with a low BFI developed less extensive biofilms and were more susceptible to azithromycin. dsDNA was present in the S. pneumoniae biofilm matrix in all strains and treatment with DNase I significantly reduced biofilm biomass. Since capsule expression has been hypothesized to be associated with decreased biofilm development, we also examined expression of cpsA, the first gene in the pneumococcal capsule operon. Interestingly, cpsA was downregulated in biofilms in both high and low BFI strains. All pneumococcal strains developed biofilms that exhibited extracellular dsDNA in the biofilm matrix, however strains with a high BFI correlated with greater carbohydrate-associated structural complexity and antibiotic resistance. Furthermore, all strains of S. pneumoniae showed downregulation of the cpsA gene during biofilm growth compared to planktonic culture, regardless of BFI ranking, suggesting downregulation of capsule expression occurs generally during adherent growth.

Metrics

14 Record Views
208 citations in Web of Science
220 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#3 Good Health and Well-Being

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Web of Science research areas
Microbiology
Logo image