Pathogenicity of exopolysaccharide‐producing Actinomyces oris isolated from an apical abscess lesion. (17th August 2012)

• Record Type: Journal Article
• Authors: Yamane, K.; Nambu, T.; Yamanaka, T.; Ishihara, K.; Tatami, T.; Mashimo, C.; Walker, C. B.; Leung, K.‐P.; Fukushima, H.
• Is Part Of: International endontic journal. Volume 46:Number 2(2013:Feb.)
• Page Start: 145
• Page End: 154
• Publication Date: 2012-08-17
• Subjects: Endodontics -- Periodicals; 617.6342
• DOI: 10.1111/j.1365-2591.2012.02099.x
• Languages: English
• ISSNs: 0143-2885

Abstract

<abstract abstract-type="main" id="iej2099-abs-0001"> <title>Abstract</title> <sec id="iej2099-sec-0001" sec-type="section"> <title>Aim</title> <p>To demonstrate a capacity for producing exopolysaccharides (EPSs) and an ability to form biofilm on abiotic materials of <italic>Actinomyces oris</italic> strain K20.</p> </sec> <sec id="iej2099-sec-0002" sec-type="section"> <title>Methodology</title> <p>The productivity of EPSs and the ability to form biofilm of strain K20 were evaluated by measuring viscosity of spent culture media and by scanning electron microscopy (SEM) and the biofilm assay on microtitre plates, respectively. High‐performance liquid chromatography was used to determine the chemical composition of the viscous materials. To examine the role of the viscous materials attributable to the pathogenicity in this organism, the ability of strain K20 to induce abscess formation was compared in mice to that of ATCC 27044.</p> </sec> <sec id="iej2099-sec-0003" sec-type="section"> <title>Results</title> <p>The viscosity of the spent culture media of K20 was significantly higher than that of ATCC 27044. Strain K20 showed dense meshwork structures around the cells and formed biofilms on microtitre plates, whereas ATCC 27044 did not. Chemical analysis of the viscous materials revealed that they were mainly composed of neutral sugars with mannose constituting 77.5% of the polysaccharides. Strain K20 induced persistent abscesses in mice lasting at least 5 days at a concentration of 10<sup>8</sup> cells mL<sup>−1</sup>, whereas abscesses induced by ATCC 27044 healed and disappeared or decreased in size at day 5.</p> </sec> <sec id="iej2099-sec-0004" sec-type="section"> <title>Conclusions</title> <p>Strain K20 produced EPSs, mainly consisting of mannose, and formed biofilms. This phenotype might play an important role for <italic>A. oris</italic> to express virulence through the progression of apical periodontitis.</p> </sec> </abstract>