doiSerbia

The effect of hydrophobicity of group a beta-hemolytic streptococcus in the process of adherence and biofilm production

Šmitran Aleksandra (University of Banja Luka, Faculty of Medicine, Department of Microbiology and Immunology, Banja Luka, Republic of Srpska, Bosnia and Herzegovina)
Marković Tatjana (Public Health Institute, Banja Luka, Republic of Srpska, Bosnia and Herzegovina)
Ranin Lazar (School of Medicine, Institute of Microbiology and Immunology, Belgrade)

Introduction. Bacterial cell hydrophobicity and adherence to a substrate are one of the most important factors in biofilm formation. Group A streptococcus is an unstable and low biofilm productor. Importance of biofilm production in streptococcal pathogenesis is still unknown. Objective. The aim of this study was to determine the impact of hydrophobicity and adherence on the biofilm production of group A streptococcal invasive and noninvasive isolates, and also to evaluate the stability of biofilm production in time function. Methods. Adherence, hydrophobicity and biofilm production were investigated in a total of 172 isolates divided into three groups: noninvasive, low invasive and highly invasive. Adherence to uncoated and laminin-coated microtiter plates and biofilm production after 12, 24 and 48 hours of incubation was determined using the method described by Stepanović et al. Hydrophobicity was measured using the MATH test by Rosenberg and SAT test by Lindhal. Results. Correlation between adherence and biofilm production was detected in the group of noninvasive isolates. These isolates were stable biofilm productors during all three time periods of biofilm production. In the groups of invasive and noninvasive isolates no statistical correlation was detected among the analysed variables. The invasive isolates were unstable biofilm productors. Conclusion. Noninvasive isolates were stable biofilm producers; as detected, they showed a direct correlation between adherence and biofilm production, and a negative impact of hydrophobicity on the biofilm production. Invasive isolates were unstable biofilm productors; it was observed that there was no correlation between adherence and hydrophobicity with biofilm production.

Keywords: adherence, hydrophobicity, biofilm, group A streptococcus

Projekat Ministarstva nauke Republike Srbije, br. 175039: Bakterije rezistentne na antibiotike u Srbiji: fenotipska i genotipska rezistencija