I. Hautefort et al., Selection of Lactobacillus fermentum strains able to durably colonize the digestive tract of mice harboring a complex human flora, FEMS MIC EC, 29(1), 1999, pp. 23-31
Sixteen Lactobacillus fermentum strains were isolated from the fecal microf
lora of pigs. They were challenged in vivo, in gnotobiotic mice harboring a
porcine flora devoid of lactobacilli. Some of the strains were able to col
onize the digestive tract of the mice at high population levels, whilst oth
er strains were eliminated. Chromosomal DNA restriction analysis performed
on both colonizing (C-type) and non-colonizing (NC-type) strains were analy
zed by pulsed-field gel electrophoresis. Strains LEMPL9 (C-type) and LEM1.1
6A (NC-type) exhibited a high degree of homology. When challenged in mice h
arboring a simplified anaerobic flora, LEMPL9 was able to colonize the dige
stive tract of the animals whereas LEM1.16A was again eliminated. Mutagenes
is performed on LEM1.16A allowed the isolation of a mutant able to colonize
the gut of mice harboring the simplified anaerobic flora or a complex huma
n flora, suggesting that genes involved in colonization process might have
been affected to enhance the bacterium's colonization ability. (C) 1999 Fed
eration of European Microbiological Societies. Published by Elsevier Scienc
e B.V. All rights reserved.