Bacterial composition of murine fecal microflora is indigenous and genetically guided

Abstract

The gastrointestinal tract and the microbes colonizing it form a complex ecosystem that has various effects on the well-being of the host. In addition to acute infections, the composition of the gastrointestinal microbiota has been suspected to influence the etiopathogenesis of many chronic diseases, such as rheumatoid arthritis and inflammatory bowel diseases. It has been suggested that the bacterial colonization of the gastrointestinal tract is genetically determined. Using gas-liquid chromatography of bacterial cellular fatty acids we show in this study that modulation of the microbiota by a course of antibiotics is followed by regeneration of the murine intestinal flora depending on the genotype of the host. The mice used in our study were acclimatized to identical living conditions before treatment with ciprofloxacin and clindamycin for 1 week via drinking water. Within a few days of finishing the antibiotic course, the cellular fatty acid profiles of fecal samples resembled those of the pre-course community, showing a considerable indigenous recovery potential. Colonization of the gastrointestinal tract appeared to be genetically regulated since differences in communities between the mouse strains were observed. Our results are in harmony with earlier observations, indicating that the gut community is not established by chance and that it is influenced by host-derived factors.

Molecular Approaches for the Study of Genetic Diversity in Microflora of Poultry Gastrointestinal Tract

“…This finding was also noted in the stool samples of other individuals (Tannock et al, 2000) and in other animals, such as dogs, chickens and mice (Zhu et al, 2002;Toivanen et al, 2001;Vaahtovuo et al, 2003). These data show the dependence of the bacterial population on the host animal's digestive system.…”

“…SSU rRNA-based profiles of several other methods, such as cellular fatty acid composition (Toivanen et al, 2001;Vaahtovuo et al, 2003) or C + G DNA content (Apajalahti et al, 2002), have been used successfully to investigate changes in bacterial populations of the gastrointestinal tract. However, compared with SSU rRNA-based methods, these methods provide no phylogenetic information.…”

Mode of Delivery Shapes Gut Colonization Pattern and Modulates Regulatory Immunity in Mice

“…Also, differences in the gut microbiota between inbred mouse strains show that it is to a great extent defined by genotype (31)(32)(33). Even though the gut microbiota is influenced by its surroundings during early life, once it is established, it remains relatively stable (34).…”

Diversity of caecal bacteria is altered in interleukin-10 gene-deficient mice before and after colitis onset and when fed polyunsaturated fatty acids

“…Studies with mice (Vaahtovuo et al, 2001(Vaahtovuo et al, , 2003Zoetendal et al, 2001;Nones et al, 2009), human IBD patients and healthy subjects (Frank et al, 2007) have shown that the host genotype affects the composition of the bacterial community of the intestine. The reduced number of caecal bacteria observed in Il10 -/-compared to C57 mice, before clinical signs of colitis, is likely to be associated with the genotype.…”