Functional Groups of Bifidoflora of Intestinal Microbiota in Associative Symbiosis of Human

Abstract

Aim. Aim of the research is the identification of functional groups of human gut bifidoflora based on analysis of the spectrum of metabolites features, proteome, bioprofile, immunoregulatory properties and the ability to differentiate «self/non-self» among the associative microbiota. Materials and methods. The materials are 260 strains ofbifidobacteria isolated from 122 intestinal microsymbiocenoses. Experimental studies were carried out using bacteriological, chromatographic and immunological methods. Statistical processing of material is carried out by means of the package Statistica 10.0 using of k-cluster analysis and discriminant method. Results. As a result ofthe work, 3 clusters containing strains of various types of bifidobacteria were identified. The first cluster was represented by B. bifidum and was characterized by the antipeptide activity of the strains with respect to FNO-a and INF-y, IL-10. In the second cluster of the B. longum culture predominated, where the parameters of the backbone factor of microsymbiocenosis, the ability to microbial recognition, antagonistic activity and production of acetic acid were significant. In the third cluster the species composition of bifidobacteria was diverse and products of butyric, caproic acids and their isoforms were the informative tests. Conclusion. The key function of bifido-flora in the regulation of the homeostasis of the intestinal biotope is realized by the formation of functional clusters, among which the first group participates in the formation of the cytokine balance, the second group is responsible for the discrimination of associative microbiota and direct protection of the biotope from pathogens, and the third is necessary to maintain the barrier metabolic function of enterocytes in the human large intestine.

Genome Sequence and Biochemical Properties of Bifidobacterium longum Strain ICIS-505, Isolated from the Intestine of a Healthy Woman

“…Bifidobacterium longum is a common member of the human gut microbiota and is frequently present at high numbers in the human gut microbiota throughout life, which is indicative of a close symbiotic host-microbe relationship (1, 2). The B.…”

Draft Genome Sequence of Bifidobacterium bifidum Strain ICIS-310, Isolated from the Feces of a Healthy 5-Year-Old Child from Orenburg, Russia

“…Bifidobacteria are important representatives of the obligate microflora of the human intestine and occupy the leading position among representatives of the indigenous microflora, forming the basis of colonization resistance of the host due to the production of antimicrobial substances and stimulation of the factors of innate and adaptive host immunity against pathogens ( 1 , 2 ). The genus Bifidobacterium is a member of the Actinobacteria phylum and Bifidobacteriaceae family ( 3 ).…”

Environmental Determination of Indigenous Bifidobacteria of the Human Intestine

“…It has been shown that they are one of the few reliable human mutualists that do not have pathogenic properties, regardless of the state of the host organism [ 9 ]. Factual materials have been accumulated, indicating that some types of bifidobacteria have stably settled in the large intestine and remain our faithful helpers, participating in the maintenance of homeostasis [ 10 ]. Note that the relatively small number of bifidobacteria in adults and the relatively small size of the genome do not reflect their functional role in microsymbiocenosis.…”

“…The specific and quantitative paucity of representatives of this taxonomic branch, established by the results of microbiome studies, indicates the phylogenetic remoteness/isolation from most pathogenic and opportunistic intestinal bacteria, which complicates the process of horizontal transfer of pathogenicity and antibiotic resistance genes between them [ 11 ]. No islands of pathogenicity have been identified in bifidobacteria to date, despite several cases of their fixation (together with other microorganisms) in some infectious and inflammatory diseases [ 10 ]. The number and diversity of intra- and extrachromosomal mobile genetic elements in bifidobacteria are small, and the peculiarities of their organization do little to facilitate their transfer to other microorganisms [ 12 , 13 ].…”

“…To date, a significant number of bifidobacteria genome sequences have been published and described [ 10 , 14 ]. However, their reasons for living in the human gut throughout life, their adaptation and survival in the gastrointestinal environment, and their physiological effects require further study.…”