IADR Abstract Archives
Effect of Benzyl Isothiocyanate on the Expression of Biofilm-associated Genes
Objectives: Antibiotic treatment results in up- or down regulation of several virulence-associated genes in bacteria. The genes encoding NADH oxidase (nox) and fibronectin-binding protein (fbp) are known to play important roles in biofilms of some oral bacterial species. The objective was to study the effect of benzyl isothiocyanate (BITC), an antimicrobial agent from miswak plant, on the expression of the genes encoding NADH oxidase (nox) and fibronectin-binding protein (fbp) in some oral streptococci.
Methods: Bacteria were grown as biofilms in brucella broth and quantified by crystal violet staining technique. Biofilms were treated with BITC for 2 hours. The folds change in mRNA expression of nox and fbp genes was determined by comparative ΔΔCt method.
Results: A. defectiva produced the highest biofilm mass followed by S. gordonii, S. mutans, G. elegans and G. adiacens. Upon BITC treatment , S. gordonii showed the highest mRNA expression for both fbp and nox genes (P<0.05). Mean (SE) folds increase in nox mRNA expression was: S. gordonii 2 (0.3), followed by S. mutans 1.25 (0.18) and A. defectiva 1.03 (0.09). Similarly for fbp, folds increase in mRNA expression was: S. gordonii 2.65 (0.03), followed by A. defectiva 2.09 (0.6), G. elegans 1.61 (0.4), and S. mutans 1.57 (0.2). G. adiacens showed the lowest mRNA levels for both fbp and nox (P<0.05).
Conclusions: Upregulation of nox and fbp genes in S. gordonii, S. mutans and A. defectiva suggests superior survival strategies by these species, while the same was not apparent in the case of G. adiacens and G. elegans. Further investigation is needed to understand molecular mechanisms of species-specific regulatory effects of BITC treatment on the expression of nox and fbp, which are critical to biofilm life of several bacterial species.
Methods: Bacteria were grown as biofilms in brucella broth and quantified by crystal violet staining technique. Biofilms were treated with BITC for 2 hours. The folds change in mRNA expression of nox and fbp genes was determined by comparative ΔΔCt method.
Results: A. defectiva produced the highest biofilm mass followed by S. gordonii, S. mutans, G. elegans and G. adiacens. Upon BITC treatment , S. gordonii showed the highest mRNA expression for both fbp and nox genes (P<0.05). Mean (SE) folds increase in nox mRNA expression was: S. gordonii 2 (0.3), followed by S. mutans 1.25 (0.18) and A. defectiva 1.03 (0.09). Similarly for fbp, folds increase in mRNA expression was: S. gordonii 2.65 (0.03), followed by A. defectiva 2.09 (0.6), G. elegans 1.61 (0.4), and S. mutans 1.57 (0.2). G. adiacens showed the lowest mRNA levels for both fbp and nox (P<0.05).
Conclusions: Upregulation of nox and fbp genes in S. gordonii, S. mutans and A. defectiva suggests superior survival strategies by these species, while the same was not apparent in the case of G. adiacens and G. elegans. Further investigation is needed to understand molecular mechanisms of species-specific regulatory effects of BITC treatment on the expression of nox and fbp, which are critical to biofilm life of several bacterial species.
