Response to alkaline stress by root canal bacteria in biofilms
- 27 February 2007
- journal article
- Published by Wiley in International Endodontic Journal
- Vol. 40 (5), 344-355
- https://doi.org/10.1111/j.1365-2591.2006.01226.x
Abstract
To determine whether bacteria isolated from infected root canals survive alkaline shifts better in biofilms than in planktonic cultures. Clinical isolates of Enterococcus faecalis, Lactobacillus paracasei, Olsenella uli, Streptococcus anginosus, S. gordonii, S. oralis and Fusobacterium nucleatum in biofilm and planktonic cultures were stressed at pH 10.5 for 4 h, and cell viability determined using the fluorescent staining LIVE/DEAD BacLight bacterial viability kit. In addition, proteins released into extracellular culture fluids were identified by Western blotting. Enterococcus faecalis, L. paracasei, O. uli and S. gordonii survived in high numbers in both planktonic cultures and in biofilms after alkaline challenge. S. anginosus, S. oralis and F. nucleatum showed increased viability in biofilms compared with planktonic cultures. Alkaline exposure caused all planktonic cultures to aggregate into clusters and resulted in a greater extrusion of cellular proteins compared with cells in biofilms. Increased levels of DnaK, HPr and fructose-1,6-bisphosphate aldolase were observed in culture fluids, especially amongst streptococci. In general, bacteria isolated from infected roots canals resisted alkaline stress better in biofilms than in planktonic cultures, however, planktonic cells appeared to use aggregation and the extracellular transport of specific proteins as survival mechanisms.Keywords
This publication has 62 references indexed in Scilit:
- Adaptive responses to antimicrobial agents in biofilmsEnvironmental Microbiology, 2005
- Quorum sensing in streptococcal biofilm formationTrends in Microbiology, 2005
- Survival strategies of infectious biofilmsTrends in Microbiology, 2005
- Sociomicrobiology: the connections between quorum sensing and biofilmsTrends in Microbiology, 2005
- Surviving the Acid Test: Responses of Gram-Positive Bacteria to Low pHMicrobiology and Molecular Biology Reviews, 2003
- The crystal structure of Escherichia coli class II fructose-1,6-bisphosphate aldolase in complex with phosphoglycolohydroxamate reveals details of mechanism and specificityJournal of Molecular Biology, 1999
- The Characterization of Two New Low Molecular Weight Proteins (LMPs) from Streptococcus pyogenesZentralblatt für Bakteriologie, 1992
- Bacterial Biofilms in Nature and DiseaseAnnual Review of Microbiology, 1987
- The antibacterial effect of camphorated paramonochlorophenol, camphorated phenol and calcium hydroxide in the treatment of infected root canalsDental Traumatology, 1985
- A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye bindingAnalytical Biochemistry, 1976