Antibiotic resistance in Lactobacillus reuteri and Lactobacillus plantarum

摘要: Lactic acid bacteria (LAB) may act as reservoirs of antibiotic resistance genes that can be transferred via the food chain or within gastrointestinal tract to pathogenic bacteria. This thesis provides data required for assessing potential risk using resistant strains LAB species Lactobacillus reuteri and plantarum processing aids probiotics. Knowledge distributions minimum inhibitory concentrations (MICs) a is needed when phenotypic method differentiate with acquired from susceptible intrinsic resistance. Controlled standardised conditions are susceptibility testing LAB, demonstrated here during evaluation Etest broth microdilution MIC determination methods used. Inoculum size incubation time were varied susceptibilities 35 six antibiotics. An increase in either parameter resulted elevated MICs all species. Antibiotic profiles determined 56 L. 121 differed by source spatial temporal origin. obtained corresponded well each other. All ampicillin, gentamicin, erythromycin clindamycin, intrinsically streptomycin. Acquired tetracycline was associated plasmid-bound tet(M). had (n=28), ampicillin (n=14), erythromycin/clindamycin (n=6) chloramphenicol (n=1). attributed mutational pbp added tet(W), erm cat(TC) antibiotics inhibiting protein synthesis. Genetic relatedness observed among high both clindamycin. The majority carried on plasmids. Traits putative transfer machineries adjacent plasmid- chromosome-located demonstrated. donor human gut investigated studying transferability gene tet(W) faecal enterococci, bifidobacteria lactobacilli. No under tested.