Pultz Nicole J, Stiefel Usha, Subramanyan Suja, Helfand Marion S, Donskey Curtis J
Research Section, Louis Stokes Cleveland Veterans Affairs Medical Center, Case Western Reserve University, Cleveland, Ohio 44106, USA.
J Infect Dis. 2005 Mar 15;191(6):949-56. doi: 10.1086/428090. Epub 2005 Feb 11.
We used a mouse model to test the hypothesis that anaerobic microbiota in the colon inhibit the establishment of vancomycin-resistant enterococci (VRE) colonization by depleting nutrients within cecal contents and limiting the association of VRE with the mucus layer. Anaerobic growth of VRE was assessed in cecal contents and cecal mucus of mice that had received treatment with subcutaneous clindamycin or saline. VRE grew to high concentrations in cecal contents of clindamycin-treated mice and in cecal mucus of both groups but not in cecal contents of saline-treated mice, unless the cecal contents were autoclaved or converted into sterile filtrates. After orogastric inoculation of VRE, clindamycin-treated mice acquired high concentrations of VRE within the mucus layer, whereas saline-treated mice did not. These results suggest that colonic microbiota inhibit VRE by producing inhibitory substances or conditions rather than by depleting nutrients. The colonic mucus layer provides a potential niche for growth of VRE.
结肠中的厌氧微生物群通过消耗盲肠内容物中的营养物质并限制耐万古霉素肠球菌（VRE）与黏液层的结合，从而抑制VRE定植的建立。在接受皮下注射克林霉素或生理盐水治疗的小鼠的盲肠内容物和盲肠黏液中评估VRE的厌氧生长。VRE在克林霉素治疗小鼠的盲肠内容物以及两组小鼠的盲肠黏液中均生长至高浓度，但在生理盐水治疗小鼠的盲肠内容物中则不生长，除非盲肠内容物经过高压灭菌或转化为无菌滤液。经口胃接种VRE后，克林霉素治疗的小鼠在黏液层中获得了高浓度的VRE，而生理盐水治疗的小鼠则没有。这些结果表明，结肠微生物群通过产生抑制物质或条件而非消耗营养物质来抑制VRE。结肠黏液层为VRE的生长提供了一个潜在的生态位。
