Cargando…
Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production
It is unclear whether Streptococcus pneumoniae in biofilms are virulent and contribute to development of invasive pneumococcal disease (IPD). Using electron microscopy we confirmed the development of mature pneumococcal biofilms in a continuous-flow-through line model and determined that biofilm for...
Autores principales: | , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2011
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3234282/ https://www.ncbi.nlm.nih.gov/pubmed/22174882 http://dx.doi.org/10.1371/journal.pone.0028738 |
_version_ | 1782218501006557184 |
---|---|
author | Sanchez, Carlos J. Kumar, Nikhil Lizcano, Anel Shivshankar, Pooja Dunning Hotopp, Julie C. Jorgensen, James H. Tettelin, Hervé Orihuela, Carlos J. |
author_facet | Sanchez, Carlos J. Kumar, Nikhil Lizcano, Anel Shivshankar, Pooja Dunning Hotopp, Julie C. Jorgensen, James H. Tettelin, Hervé Orihuela, Carlos J. |
author_sort | Sanchez, Carlos J. |
collection | PubMed |
description | It is unclear whether Streptococcus pneumoniae in biofilms are virulent and contribute to development of invasive pneumococcal disease (IPD). Using electron microscopy we confirmed the development of mature pneumococcal biofilms in a continuous-flow-through line model and determined that biofilm formation occurred in discrete stages with mature biofilms composed primarily of dead pneumococci. Challenge of mice with equal colony forming units of biofilm and planktonic pneumococci determined that biofilm bacteria were highly attenuated for invasive disease but not nasopharyngeal colonization. Biofilm pneumococci of numerous serotypes were hyper-adhesive and bound to A549 type II pneumocytes and Detroit 562 pharyngeal epithelial cells at levels 2 to 11-fold greater than planktonic counterparts. Using genomic microarrays we examined the pneumococcal transcriptome and determined that during biofilm formation S. pneumoniae down-regulated genes involved in protein synthesis, energy production, metabolism, capsular polysaccharide (CPS) production, and virulence. We confirmed these changes by measuring CPS by ELISA and immunoblotting for the toxin pneumolysin and the bacterial adhesins phosphorylcholine (ChoP), choline-binding protein A (CbpA), and Pneumococcal serine-rich repeat protein (PsrP). We conclude that biofilm pneumococci were avirulent due to reduced CPS and pneumolysin production along with increased ChoP, which is known to bind C-reactive protein and is opsonizing. Likewise, biofilm pneumococci were hyper-adhesive due to selection for the transparent phase variant, reduced CPS, and enhanced production of PsrP, CbpA, and ChoP. These studies suggest that biofilms do not directly contribute to development of IPD and may instead confer a quiescent mode of growth during colonization. |
format | Online Article Text |
id | pubmed-3234282 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2011 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-32342822011-12-15 Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production Sanchez, Carlos J. Kumar, Nikhil Lizcano, Anel Shivshankar, Pooja Dunning Hotopp, Julie C. Jorgensen, James H. Tettelin, Hervé Orihuela, Carlos J. PLoS One Research Article It is unclear whether Streptococcus pneumoniae in biofilms are virulent and contribute to development of invasive pneumococcal disease (IPD). Using electron microscopy we confirmed the development of mature pneumococcal biofilms in a continuous-flow-through line model and determined that biofilm formation occurred in discrete stages with mature biofilms composed primarily of dead pneumococci. Challenge of mice with equal colony forming units of biofilm and planktonic pneumococci determined that biofilm bacteria were highly attenuated for invasive disease but not nasopharyngeal colonization. Biofilm pneumococci of numerous serotypes were hyper-adhesive and bound to A549 type II pneumocytes and Detroit 562 pharyngeal epithelial cells at levels 2 to 11-fold greater than planktonic counterparts. Using genomic microarrays we examined the pneumococcal transcriptome and determined that during biofilm formation S. pneumoniae down-regulated genes involved in protein synthesis, energy production, metabolism, capsular polysaccharide (CPS) production, and virulence. We confirmed these changes by measuring CPS by ELISA and immunoblotting for the toxin pneumolysin and the bacterial adhesins phosphorylcholine (ChoP), choline-binding protein A (CbpA), and Pneumococcal serine-rich repeat protein (PsrP). We conclude that biofilm pneumococci were avirulent due to reduced CPS and pneumolysin production along with increased ChoP, which is known to bind C-reactive protein and is opsonizing. Likewise, biofilm pneumococci were hyper-adhesive due to selection for the transparent phase variant, reduced CPS, and enhanced production of PsrP, CbpA, and ChoP. These studies suggest that biofilms do not directly contribute to development of IPD and may instead confer a quiescent mode of growth during colonization. Public Library of Science 2011-12-08 /pmc/articles/PMC3234282/ /pubmed/22174882 http://dx.doi.org/10.1371/journal.pone.0028738 Text en Sanchez et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Sanchez, Carlos J. Kumar, Nikhil Lizcano, Anel Shivshankar, Pooja Dunning Hotopp, Julie C. Jorgensen, James H. Tettelin, Hervé Orihuela, Carlos J. Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production |
title |
Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production |
title_full |
Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production |
title_fullStr |
Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production |
title_full_unstemmed |
Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production |
title_short |
Streptococcus pneumoniae in Biofilms Are Unable to Cause Invasive Disease Due to Altered Virulence Determinant Production |
title_sort | streptococcus pneumoniae in biofilms are unable to cause invasive disease due to altered virulence determinant production |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3234282/ https://www.ncbi.nlm.nih.gov/pubmed/22174882 http://dx.doi.org/10.1371/journal.pone.0028738 |
work_keys_str_mv | AT sanchezcarlosj streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT kumarnikhil streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT lizcanoanel streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT shivshankarpooja streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT dunninghotoppjuliec streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT jorgensenjamesh streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT tettelinherve streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction AT orihuelacarlosj streptococcuspneumoniaeinbiofilmsareunabletocauseinvasivediseaseduetoalteredvirulencedeterminantproduction |