Adhesive properties and extracellular enzymatic activity of Staphylococcus aureus strains isolated from oral cavity.
Staphylococcus aureus is one of prominent bacterial pathogen that occurs in oral region. In this study, 21 strains of S. aureus isolated from the oral cavity of Tunisian patients were investigated for slime production using Congo red agar method (CRA) and adherence assay. Biofilm formation of oral isolates on orthodontic biomaterials (Bis-GMA and PMMA) was also evaluated by MTT reduction assay. In addition, the production of hydrolytic enzymes by S. aureus strains was analyzed and the presence of protease, lipase and β-hemolysin genes (sspA, sspB, geh, hlb) was achieved by polymerase chain reaction (PCR). Qualitative biofilm production tested on CRA revealed that 91% of strains were slime producers. The result of OD570 showed that five strains isolated from the oral cavity were highly biofilm positive. The metabolic activity of S. aureus biofilm formed on Bis-GMA and PMMA did not differ between tested strains. The atomic force micrographs demonstrated that biofilm formed by S. aureus strains was organized in typical cocci cells attached to each other through production of exopolymeric substances. The production of hydrolytic enzymes showed that all S. aureus strains were protease positive. Lipase (77%) and beta hemolytic (59%) activities were also detected. Among the tested strains, 17 were positive for sspA, sspB and hlb genes. While only ten S. aureus strains harbor the geh gene (48%). These data highlight the importance of evaluation of biofilm formation and exoenzyme production in oral S. aureus isolates to investigate the role of this pathogen and its impact in oral pathology.
Laboratoire des Maladies Transmissible et substances biologiquement actives « LR99ES27», Faculté de Pharmacie, Avenue Avicenne, 5000 de Monastir, Tunisia. Electronic address: abderrahmen_merghni@yahoo.fr.
Abderrahmen
A
Merghni
Laboratoire des Maladies Transmissible et substances biologiquement actives « LR99ES27», Faculté de Pharmacie, Avenue Avicenne, 5000 de Monastir, Tunisia.
Mouna
M
Ben Nejma
Service de Médecine et chirurgie buccales, Clinique hospitalo-universitaire d'Odontologie, Monastir, Tunisia.
Hajer
H
Hentati
Laboratoire des Maladies Transmissible et substances biologiquement actives « LR99ES27», Faculté de Pharmacie, Avenue Avicenne, 5000 de Monastir, Tunisia.
Aouni
A
Mahjoub
Laboratoire des Maladies Transmissible et substances biologiquement actives « LR99ES27», Faculté de Pharmacie, Avenue Avicenne, 5000 de Monastir, Tunisia; Laboratoire de Microbiologie, CHU Fatouma Bourguiba, de Monastir, Tunisia.
Maha
M
Mastouri
D000328:Adult; D001422:Bacterial Adhesion; D001431:Bacteriological Techniques; D018441:Biofilms / Q000254:growth & development*; D005260:Female; D006801:Humans; D006867:Hydrolases / Q000235:genetics / Q000378:metabolism*; D008297:Male; D018625:Microscopy, Atomic Force; D008875:Middle Aged; D009055:Mouth / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000302:isolation & purification / Q000502:physiology*; D014416:Tunisia
D006867:Hydrolases
Biofilm; Hydrolytic enzymes; Orthodontic biomaterials; Staphylococcus aureus