How far is the effect of Subminimal Inhibitory Concentration (Sub MIC) on virulence factors expressed by bacteria?

Nidaa M A Wadi

Abstract

Antibiotic medications are widely used in the treatment and prevention of various infections. An increase in the rate and extent of antibacterial action can be ranged over a wide of antimicrobial concentration but should be within minimum inhibitory concentration where this concentration represents the minimum effective of antibacterial agent (MIC). Sub inhibitory antimicrobial concentration (Sub MIC) may produce antibacterial effect. The major virulence factors associated with infections are the ability to adhere to tissue and initiates interaction of bacterial cell with tissue. It is potential in the pathogenesis of certain infectious disease. Agents interfering with the process of bacterial adhesion may have beneficial prophylactic or therapeutic effects. Many studies indicate that certain antibiotics affect bacterial adhesion at low concentrations. Sub inhibitory concentrations (Sub MIC) of some antibiotics may have an effect on bacterial structure and influence the adhesion of bacterial adhesion to epithelial cells. It has been observed that the pili play an important role in the attachment and an important prerequisite factor for the pathogenesis of the bacteria. Various antibiotics in Sub MIC concentrations markedly impair adhesion of Streptococcus pyogenes and Escherichia coli to human cells like loss of lipoteichoic acid that binds the organism to host cells. In this study certain characters of the isolated pathogen in vitro and the presence and absence of pili on the surface of the organism were studied. We utilized an in vitro assay system to study the effect of Sub MIC of various antibiotics on Escherichia coli. The results demonstrate that some antibiotics change the adhesiveness of Escherichia coli strains. Subminimum inhibitory concentration of various antibiotics showed the ability to reduce the colonization. Investigating the effects of Sub MIC antibiotics bacterial adhesion to epithelial cells may lead to the development of future antibiotic treatment modalities and may suggest a new parameter for the use and the study of antibacterial agents.