Implantation of bacteria from the digestive tract of man and various animals into gnotobiotic mice

Abstract

Fourteen microbial strains isolated from conventional rats were inoculated into axenic rats and mice receiving identical diets. The populations of these organisms which became established in the feces of gnotobiotic adult recipient rats and mice were quite similar. The only major difference was that one strain, belonging to the genus Clostridium, disappeared from the feces of gnotobiotic mice, whereas this strain became established in gnotobiotic rats. Most of the strictly anaerobic strains were absent or present only in small numbers before weaning in young rats and mice. A clear-cut barrier effect against Salmonella typhimurium was found in adult gnotobiotic mice colonized with a complex flora derived from a conventional chicken. The microflora established in these recipient mice exerted the same barrier effect when further transferred into axenic chickens. Inoculation of feces from a human donor into adult gnotobiotic recipient mice produced colonization by several strains from the donor, whereas other strains, belonging to the genera Bifidobacterium, Lactobacillus, and Clostridium were present in the donor, but did not persist in recipient mice. In these mice, nonetheless, the colonizing human fecal flora exerted an effective barrier against a toxigenic strain of Clostridium difficile. This barrier effect spontaneously disappeared several weeks later. Administration of clindamycin to the recipient mice led to large variations in the number of viable cells of C. difficile.

Inter-species transplantation of gut microbiota from human to pigs

“…Molecular techniques that do not require isolation of bacterial strains, such as ERIC-PCR fingerprinting, TGGE/denaturing gradient gel electrophoresis (DGGE) analysis, 16S rRNA gene clone library profiling and real-time PCR, were utilized to analyze the microbiota in the gut of the HFA piglets. Previous studies on the microbiota composition of HFA animals were based on traditional culture methods (Raibaud et al, 1980;Hazenberg et al, 1981;Mallett et al, 1987;Hirayama, 1999), which underestimate the abundance of the bacterial populations and thus provide an incomplete picture of the composition of the microflora. Use of the abovementioned molecular methods will yield more detailed information about the microbiota and will provide a more comprehensive comparison of the microbiota in the HFA animals and the human donor.…”

“…Such HFA animal model has significantly facilitated progress in researches of human gut ecology, metabolism and immunity (Hazenberg et al, 1981;Roland et al, 1996;Oozeer et al, 2002;Gerard et al, 2004;Wilcks et al, 2004). However, owing to the significant differences in basic anatomy and physiology of rodents to human, key members of human gut microbiota such as bifidobacteria do not colonize the rodent gut; and rodents do not develop a full repertoire of immune responses unless some rodent-specific gut bacteria are reintroduced back into the gut (Raibaud et al, 1980;Imaoka et al, 2004). Thus, results obtained from these mice/rat models often have low relevance to human beings.…”

Bacterial populations in juvenile maize rhizospheres originate from both seed and soil

“…Seed endophytes have been shown to colonize grass seedlings (Johnston-Monje et al 2014;Hardoim et al 2012;Rijavec et al 2007), travel within the plant and even exit the roots and colonize the rhizosphere (Johnston-Monje and Raizada 2011a; Hardoim et al 2012). Seed transmitted microbes colonizing the rhizosphere would be guaranteed first access to that habitat, perhaps creating a founder effect, blocking later colonization by less adapted soil microbes (Ait Barka et al 2002;Bacilio-Jimenez et al 2001;Raibaud et al 1980). Seed epiphytes should have no barrier to getting on root surfaces, however endophytes might struggle to exit the plant in order to gain access to the rhizosphere; a newly discovered mechanism endophytes might use to do this involves root border cells containing intracellular populations of bacteria that are sloughed off and released into the surrounding substrate almost like little water balloons full of inoculant (Cope-Selby 2013).…”

Recovery of spores of Clostridium difficile altered by heat or alkali

“…Survival of C. dificile in an aerobic environment is possible because this obligate anaerobe can form aerotolerant spores; there are reports that C. dzficile can survive for > 5 months in aerobic conditions (Kim et al, 1981). Although it is well known that C. dificile spores cannot be effectively recovered in ordinary growth medium (Raibaud et al, 1980), their recovery is distinctly enhanced when they are treated with sodium thioglycollate and inoculated in lysozyme containing media (Ionesco, 1978 ;Nakamura et al, 1985). It has also been reported that addition of sodium taurocholate to media resulted in good spore recovery (Raibaud et al, 1980;Wilson et al, 1982) and sodium taurocholate-containing medium has been shown to be useful for detection of C. dificile spores, particularly when faecal specimens have not been handled optimally or when vegetative forms have lost viability after prolonged exposure to air (Buggy et al, 1983(Buggy et al, , 1985Wilson, 1983).…”