Experimental Evaluation of Host Adaptation of Lactobacillus reuteri to Different Vertebrate Species

作者：Rebbeca M. Duar, Steven A. Frese, Xiaoxi B. Lin, Samodha C. Fernando, T. E. Burkey, Guergana Tasseva, Daniel A. Peterson, Jochen Blom, Cory Q. Wenzel, Christine M. Szymanski, Jens Walter · 发表于：Applied and Environmental Microbiology · 年份：2017 · DOI：10.1128/aem.00132-17 · 被引用次数：110 · 研究领域：Probiotics and Fermented Foods、Gut microbiota and health、Clostridium difficile and Clostridium perfringens research

ABSTRACT The species Lactobacillus reuteri has diversified into host-specific lineages, implying a long-term association with different vertebrates. Strains from rodent lineages show specific adaptations to mice, but the processes underlying the evolution of L. reuteri in other hosts remain unknown. We administered three standardized inocula composed of strains from different host-confined lineages to mice, pigs, chickens, and humans. The ecological performance of each strain in the gastrointestinal tract of each host was determined by typing random colonies recovered from fecal samples collected over five consecutive days postadministration. Results revealed that rodent strains were predominant in mice, confirming previous findings of host adaptation. In chickens, poultry strains of the lineage VI (poultry VI) and human isolates from the same lineage (human VI) were recovered at the highest and second highest rates, respectively. Interestingly, human VI strains were virtually undetected in human feces. These findings, together with ancestral state reconstructions, indicate poultry VI and human VI strains share an evolutionary history with chickens. Genomic analysis revealed that poultry VI strains possess a large and variable accessory genome, whereas human VI strains display low genetic diversity and possess genes encoding antibiotic resistance and capsular polysaccharide synthesis, which might have allowed temporal colonization of humans. Experiments in pigs and humans did...