Affiliation:
1. Unité Flore Lactique et Environnement Carné, UR309
2. Unité Ecologie et Physiologie du Système Digestif, UR902, INRA, Domaine de Vilvert, F78350 Jouy en Josas, France
Abstract
ABSTRACT
A
Lactobacillus sakei
strain named FLEC01 was isolated from human feces and characterized genotypically. Comparison of the genetic features of this strain with those of both the meat-borne
L. sakei
strain 23K and another human isolate, LTH5590, showed that they belong to different but closely related clusters. The three
L. sakei
strains did not persist and only transited through the gastrointestinal tracts (GITs) of conventional C3H/HeN mice. In contrast, they all colonized the GITs of axenic mice and rapidly reached a population of 10
9
CFU/g of feces, which remained stable until day 51. Five days after mice were fed, a first subpopulation, characterized by small colonies, appeared and reached 50% of the total
L. sakei
population in mice. Fifteen to 21 days after feeding, a second subpopulation, characterized by rough colonies, appeared. It coexisted with the two other populations until day 51, and its cell shapes were also affected, suggesting a dysfunction of the cell division or cell wall. No clear difference between the behaviors of the meat-borne strain and the two human isolates in both conventional and axenic mice was observed, suggesting that
L. sakei
is a food-borne bacterium rather than a commensal one and that its presence in human feces originates from diet. Previous observations of
Escherichia coli
strains suggest that the mouse GIT environment could induce mutations to increase their survival and colonization capacities. Here, we observed similar mutations concerning a food-grade gram-positive bacterium for the first time.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Cited by
24 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献