Partial characterization of antagonistic substance produced by a Clostridium butyricum strain

Abstract

The production of antagonistic substance by bacterium present in the infected root canal system (RCS) probably is an important ecological factor for its successful colonization of the local. The objective of this study was to partially characterize an antagonistic substance produced by a Clostridium butyricum isolated from infected RCS. Production of inhibitory compound was evaluated by the agar double layer diffusion technique using Fusobacterium nucleatum and Bifidobacterium adolescentis as indicator bacteria. The physicochemical and biochemical factors tested for the partial characterization were influence of pH and temperature and susceptibility to the action of some proteolytic enzymes. An inhibition zone was observed against the two indicator strains and acidity and bacteriophage were rejected as responsible for this phenomenon. The inhibitory activity showed to be decreasing in a pH range from 3.5 to 6.5 and being stable at temperatures of 60º, 70º and 100ºC, but completely inactivated when exposed at 121ºC. The antagonistic activity was resistant to the proteolytic action of trypsin, α-chymotrypsin and papain. An antagonistic substance was produced by C. butyricum, which was thermo-resistant and probably of non-protein nature.

Synergistic growth effect among bacteria recovered from root canal infections

“…Several studies have been assayed bacterial antagonistic activity in root canal microbiota (3,21). According to Klaenhammer (14), lactic acid bacteria produce antibacterial substances that vary in their spectrum of activity, mode of action, molecular mass, genetic determinants, and biochemical characteristics.…”

“…Most previous studies examining the ecological complexity of root canal infections have shown antagonistic bacterial activity in these sites (2,3,16,21). The present study…”

Cytokine expression in response to root canal infection in gnotobiotic mice

“…1998, Peters et al. 2002, Socransky & Haffajje 2005), are important factors in the establishment and colonization of the root canal (Caires et al. 2007, Sundquivst & Figdor 2007).…”

“…2007, Sundquivst & Figdor 2007). Synergism occurs when the metabolism of a species produces nutrients and growth factors that are reliable food sources for another species, whilst antagonism occurs when a microorganism produces substances that may be toxic to or inhibit the growth of another species (Sundqvist 1992, Caires et al. 2007).…”

“…Selective environmental pressures (Sundqvist 1992, Siqueira et al 2009) present in root canals, such as nutrients, oxygen availability and microbial interactions contribute to the anaerobic status of invading bacteria. Additionally, microbial interactions, which can be synergistic or antagonistic (Oliveira et al 1998, Socransky et al 1998, Peters et al 2002, Socransky & Haffajje 2005, are important factors in the establishment and colonization of the root canal (Caires et al 2007, Sundquivst & Figdor 2007. Synergism occurs when the metabolism of a species produces nutrients and growth factors that are reliable food sources for another species, whilst antagonism occurs when a microorganism produces substances that may be toxic to or inhibit the growth of another species (Sundqvist 1992, Caires et al 2007).…”