Biofilm Mode of Growth of Streptococcus intermedius Favored by a Competence-Stimulating Signaling Peptide

Abstract

Gram-positive and gram-negative bacteria use quorum sensing to coordinate population behavior. In several streptococci, quorum sensing mediated by competence-stimulating peptides (CSP) is associated with development of competence for transformation. We show here that a synthetic CSP favored the biofilm mode of growth of Streptococcus intermedius without affecting the rate of culture growth.

The cidA murein hydrolase regulator contributes to DNA release and biofilm development in Staphylococcus aureus

“…DNase treatment has been shown to disrupt P. aeruginosa biofilm grown in vitro (35,46) and is used in combination with antibiotics to treat P. aeruginosa infections of cystic fibrosis patients (47). Treatment of streptococcal biofilm with DNase has also been shown to have a negative effect on biofilm adherence (41,48,49). These results correlate with our findings that DNase treatment had a greater ability to interfere with biofilm adherence in the wild-type S. aureus strain relative to the cidA mutant, presumably because the mutant biofilm contains less eDNA (Figs.…”

Long-term bacterial exposure can trigger nonsuppurative destructive cholangitis associated with multifocal epithelial inflammation

“…26 These microorganisms grow preferentially in the oral cavity, attaching to a surface, forming matrix-enclosed biofilms, and thereby exhibiting increased resistance to antimicrobials and to host immune defense mechanisms. 27 It is possible that, except for cases, which were severe lethal infection, most of these bacteria would remain in place, and provide a chronic and silent pathogen supply with which the status of PBC could mature. Supporting this notion, viridans group streptococci were actually detected from PBC patients' oral mucosa (unpublished observation).…”

“…16 In the oral cavity, for instance, streptococci constitute approximately 60% of the initial biofilm microflora on the tooth surface. 17 Considering these observations, we speculated that some bacterial components originating from asymptomatic or less apparent chronic bacterial infection might have function(s) in the initiation and/or development of the autoimmune status in patients with PBC, eventually leading to chronic epithelial inflammation in the liver and multiple epithelial inflammation. Recently, a strain with a dominant-negative form of TGFb receptor II, 18 IL-2 receptor a À/À mice, 19 and Ae2 a,b -deficient mice 20 have been reported as spontaneous PBC animal models.…”

Inhibition ofSteptococcus mutansbiofilm formation by extracts ofTenacibaculumsp. 20J, a bacterium with wide-spectrum quorum quenching activity

“…Biofilm formation by S. mutans is regulated by two QS systems, although the hierarchy of their organization is unknown. The QS system typical of streptococci is regulated by a peptide pheromone signal called competence stimulating peptide (CSP) [9], which is species-specific and detected by a histidine-kinase [10]. The inactivation of any of the genes related to the CSP QS system results in the alteration of biofilm architecture [11].…”