CULTIVATION OF BORDETELLA PERTUSSIS BIOFILMS ON ABIOTIC SUBSTRATE

Abstract

Aim. Selection of optimal conditions for the cultivation of Bordetella pertussis biofilms and comparative assessment of the ability of different strains to form biofilms. Materials and methods. Used a vaccine strain of B. pertussis № 475 and selected from this strain strain № 475а, characterized by high virulence. Cultures of strains grown on dense nutrient medium (DNM) and liquid nutrient medium (LNM) were used as inoculates for biofilms production. The intensity of biofilms formation in round-bottom 96-well polystyrene plates was estimated by staining with 0,1% gentian-violet solution. Results. Daily cultures of the strain № 475 with LNM formed moderate biofilms in the range of doses 5 — 1,25 IOU (international optical units) /ml, in the absence of growth at lower doses. The daily cultures of this strain with the DNM formed a dense biofilms when planting a doses in the range from 10 to 1,25 IOU/ml, moderate from 0,625 to 0,157 IOU/ml and weak biofilms at a dose of 0,079 IOU/ml. Strain № 475а with the DNM formed dense biofilms in the doses range of 10 to 0,04 IOU/ml and only at the dose of 0,02 IOU/ml were formed moderate biofilms. Conclusion. A simple and informative method has been developed to evaluate the ability of B. pertussis strains to form biofilms in polystyrene plates. Cultures obtained with the DNM formed a more significant biofilms than cultures with LNM. Identified high ability to biofilms formation by a selected strain №. 475a, compared to the original strain № 475.