The family Bifidobacteriaceae constitutes an important phylogenetic group that particularly includes bifidobacterial taxa demonstrating proven or debated positive effects on host health. The increasingly widespread application of probiotic cultures in the twenty-first century requires detailed classification to the level of particular strains. This study aimed to apply the glutamine synthetase class I (glnAI) gene region (717 bp representing approximately 50% of the entire gene sequence) using specific PCR primers for the classification, typing, and phylogenetic analysis of bifidobacteria and closely related scardovial genera. In the family Bifidobacteriaceae, this is the first report on the use of this gene for such purposes. To achieve high-value results, almost all valid Bifidobacteriaceae type strains (75) and 15 strains isolated from various environments were evaluated. The threshold value of the glnAI gene identity among Bifidobacterium species (86.9%) was comparable to that of other phylogenetic/identification markers proposed for bifidobacteria and was much lower compared to the 16S rRNA gene. Further statistical and phylogenetic analyses suggest that the glnAI gene can be applied as a novel genetic marker in the classification, genotyping, and phylogenetic analysis of isolates belonging to the family Bifidobacteriaceae.
- MeSH
- Genes, Bacterial MeSH
- Bifidobacterium classification enzymology MeSH
- DNA, Bacterial genetics MeSH
- DNA Primers MeSH
- Phylogeny * MeSH
- Genetic Markers MeSH
- Genotype MeSH
- Glutamate-Ammonia Ligase genetics MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Bacterial Typing Techniques MeSH
- Publication type
- Journal Article MeSH
A fructose-6-phosphate phosphoketolase-positive strain (GSD1FST) was isolated from a faecal sample of a 3 weeks old German Shepherd dog. The closest related taxa to isolate GSD1FST based on results from the EZBioCloud database were Bifidobacterium animalis subsp. animalis ATCC 25527T, Bifidobacterium animalis subsp. lactis DSM 10140T and Bifidobacterium anseris LMG 30189T, belonging to the Bifidobacterium pseudolongum phylogenetic group. The resulting 16S rRNA gene identities (compared length of 1454 nucleotides) towards these taxa were 97.30, 97.23 and 97.09 %, respectively. The pairwise similarities of strain GSD1FST using argS, atpA, fusA, hsp60, pyrG, rpsC, thrS and xfp gene fragments to all valid representatives of the B. pseudolongum phylogenetic group were in the concatenated range of 83.08-88.34 %. Phylogenomic analysis based on whole-genome methods such as average nucleotide identity revealed that bifidobacterial strain GSD1FST exhibits close phylogenetic relatedness (88.17 %) to Bifidobacetrium cuniculi LMG 10738T. Genotypic characteristics and phylogenetic analyses based on nine molecular markers, as well as genomic and comparative phenotypic analyses, clearly proved that the evaluated strain should be considered as representing a novel species within the B. pseudolongum phylogenetic group named as Bifidobacterium canis sp. nov. (GSD1FST=DSM 105923T=LMG 30345T=CCM 8806T).
- MeSH
- Aldehyde-Lyases MeSH
- Genes, Bacterial MeSH
- Bifidobacterium classification MeSH
- DNA, Bacterial genetics MeSH
- Feces microbiology MeSH
- Phylogeny * MeSH
- Dogs microbiology MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Bacterial Typing Techniques MeSH
- Base Composition MeSH
- Animals MeSH
- Check Tag
- Dogs microbiology MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
In the modern era, molecular genetic techniques are crucial in ecological studies, as well as in the classification, typing, and phylogenetic analysis of prokaryotes. These techniques are mainly aimed at whole genome comparisons and PCR-derived experiments, including amplifying the 16S rRNA and other various housekeeping genes used in taxonomy, as well as MLST (multilocus sequence typing) and MLSA (multilocus sequence analysis) of different taxonomic bacterial groups. The gene encoding threonine-tRNA ligase (thrS) is a gene potentially applicable as an identification and phylogenetic marker in bacteria. It is widely distributed in bacterial genomes and is subject to evolutionary selection pressure due to its important function in protein synthesis. In this study, specific primers were used to amplify a thrS gene fragment (~740 bp) in 36 type and 30 wild strains classified under family Bifidobacteriaceae. The full-length gene has not yet been considered as a possible identification, classification, and phylogenetic marker in bifidobacteria. The thrS sequences revealed higher sequence variability (82.7% of pairwise identities) among members of the family than that shown by 16S rRNA gene sequences (96.0%). Although discrepancies were found between the thrS-derived and previously reported whole genome phylogenetic analyses, the main phylogenetic groups of bifidobacteria were properly assigned. Most wild strains of bifidobacteria were better differentiated based on their thrS sequences than on their 16S rRNA gene identities. Phylogenetic confidence of the evaluated gene with respect to other alternative genetic markers widely used in taxonomy of bifidobacteria (fusA, GroELhsp60, pyrG, and rplB genes) was confirmed using the localized incongruence difference - Templeton analysis.
- MeSH
- Genes, Bacterial MeSH
- Bacterial Proteins genetics MeSH
- Bifidobacterium classification enzymology genetics MeSH
- DNA, Bacterial genetics MeSH
- Phylogeny * MeSH
- Multilocus Sequence Typing MeSH
- DNA, Ribosomal genetics MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Bacterial Typing Techniques MeSH
- Threonine-tRNA Ligase genetics MeSH
- Publication type
- Journal Article MeSH
Occurrence of bifidobacteria, known as health-promoting probiotic microorganisms, in the digestive tract of wild pigs (Sus scrofa) has not been examined yet. One hundred forty-nine fructose-6-phosphate phosphoketolase positive bacterial strains were isolated from colonic content of twenty-two individuals of wild pigs originated from four localities in the Czechia. Based on PCR-DGGE technique targeting the variable V3 region of the 16S rRNA genes, strains were initially differentiated into four groups represented by: (i) probably a new Bifidobacterium species (89 strains), (ii) B. boum/B. thermophilum/B. thermacidophilum subsp. porcinum/B. thermacidophilum subsp. thermacidophilum (sub)species (49 strains), (iii) Pseudoscardovia suis (7 strains), and (iv) B. pseudolongum subsp. globosum/B. pseudolongum subsp. pseudolongum (4 strains), respectively. Given the fact that DGGE technique did not allow to differentiate the representatives of thermophilic bifidobacteria and B. pseudolongum subspecies, strains were further classified by the 16S rRNA and thrS gene sequences. Primers targeting the variable regions of the latter gene were designed to be applicable in identification and phylogeny of Bifidobacteriaceae family. The 16S rRNA-derived phylogenetic study classified members of the first group into five subgroups in a separated cluster of thermophilic bifidobacteria. Comparable results were obtained by the thrS-derived phylogenetic analysis. Remarkably, variability among thrS sequences was higher compared with 16S rRNA gene sequences. Overall, molecular genetic techniques application allowed to identify a new Bifidobacterium phylotype which is predominant in the digestive tract of examined wild pigs.
- MeSH
- Genes, Bacterial MeSH
- Bifidobacterium chemistry classification genetics isolation & purification MeSH
- Animals, Wild * MeSH
- Phylogeny MeSH
- Gastrointestinal Tract microbiology MeSH
- Molecular Typing * methods MeSH
- Swine MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Sus scrofa microbiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Fresh samples of intestinal contents of three wild pigs originating from the Central Bohemia region were examined for the presence of bifidobacterial strains. During the study, we isolated many fructose-6-phosphate phosphoketolase-positive, strictly anaerobic, irregular rod-shaped bacterial isolates. Three of them were preliminarily identified as representing a novel species of the genus Bifidobacterium because their 16S rRNA gene sequence similarity with the closest relatives of thermophilic bifidobacteria (Bifidobacterium boum DSM 20432T, Bifidobacterium thermophilum DSM 20210T, Bifidobacterium thermacidophilumsubsp. porcinum LMG 21689T, Bifidobacterium thermacidophilumsubsp. thermacidophilum DSM 15837T) was in the range of 97.9 - 98.4 %. All three bacterial isolates had identical 16S rRNA, dnaJ1, fusA, gyrB and rplB gene sequences. Isolate RP115T was chosen as a representative of the bacterial group and DNA G+C content (mol%) determination, biochemical tests and analyses of physiological and morphological characteristics, habitat and chemotaxonomic traits (peptidoglycan structure, cellular fatty acids and polar lipids profile) were performed. The DNA-DNA hybridization analyses of RP115T and species representing the group of thermophilic bifidobacteria revealed values in the range from 33 to 53 %. This fact, together with relatively low sequence similarities of particular phylogenetic markers among examined bacterial strains and the phenotyping and chemotaxonomy results obtained, indicated that the evaluated bacterial isolate should be classified as representing a separate taxon within the specific group of thermophilic bifidobacteria. The name Bifidobacterium apri (of boar) sp. nov. has been proposed for the representative strain RP115T (=CCM 8605T=DSM 100238T=LMG 28779T).
- MeSH
- Aldehyde-Lyases chemistry MeSH
- Genes, Bacterial MeSH
- Bifidobacterium classification genetics isolation & purification MeSH
- DNA, Bacterial genetics MeSH
- Phylogeny * MeSH
- Nucleic Acid Hybridization MeSH
- Fatty Acids chemistry MeSH
- Peptidoglycan chemistry MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Intestines microbiology MeSH
- Sus scrofa microbiology MeSH
- Bacterial Typing Techniques MeSH
- Base Composition MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
BACKGROUND: Reduced microbial diversity has been associated with inflammatory bowel disease (IBD) and probiotic bacteria have been proposed for its prevention and/or treatment. Nevertheless, comparative studies of strains of the same subspecies for specific health benefits are scarce. Here we compared two Bifidobacterium longum ssp. longum strains for their capacity to prevent experimental colitis. METHODS: Immunomodulatory properties of nine probiotic bifidobacteria were assessed by stimulation of murine splenocytes. The immune responses to B. longum ssp. longum CCM 7952 (Bl 7952) and CCDM 372 (Bl 372) were further characterized by stimulation of bone marrow-derived dendritic cell, HEK293/TLR2 or HEK293/NOD2 cells. A mouse model of dextran sulphate sodium (DSS)-induced colitis was used to compare their beneficial effects in vivo. RESULTS: The nine bifidobacteria exhibited strain-specific abilities to induce cytokine production. Bl 372 induced higher levels of both pro- and anti-inflammatory cytokines in spleen and dendritic cell cultures compared to Bl 7952. Both strains engaged TLR2 and contain ligands for NOD2. In a mouse model of DSS-induced colitis, Bl 7952, but not Bl 372, reduced clinical symptoms and preserved expression of tight junction proteins. Importantly, Bl 7952 improved intestinal barrier function as demonstrated by reduced FITC-dextran levels in serum. CONCLUSIONS: We have shown that Bl 7952, but not Bl 372, protected mice from the development of experimental colitis. Our data suggest that although some immunomodulatory properties might be widespread among the genus Bifidobacterium, others may be rare and characteristic only for a specific strain. Therefore, careful selection might be crucial in providing beneficial outcome in clinical trials with probiotics in IBD.
- MeSH
- Bifidobacterium classification physiology MeSH
- Dendritic Cells microbiology pathology MeSH
- HEK293 Cells MeSH
- Immunoenzyme Techniques MeSH
- Colitis chemically induced prevention & control MeSH
- Humans MeSH
- Disease Models, Animal * MeSH
- Mice, Inbred BALB C MeSH
- Mice MeSH
- Probiotics pharmacology MeSH
- Nod2 Signaling Adaptor Protein genetics metabolism MeSH
- Dextran Sulfate toxicity MeSH
- Intestines microbiology physiopathology MeSH
- Toll-Like Receptor 2 genetics metabolism MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
At present, the genus Bifidobacterium includes 48 species and subspecies, and this number is expected to increase. Bifidobacteria are found in different ecological niches. However, most were originally isolated from animals, mainly mammals, especially during the milk feeding period of life. Their presence in high numbers is associated with good health of the host. Moreover, bifidobacteria are often found in poultry and insects that exhibit a social mode of life (honeybees and bumblebees). This review is designed as a summary of currently known species of the genus Bifidobacterium, especially focused on their difference and similarities. The primary focus is on their occurrence in the digestive tract of animals, as well as the specificities of animal strains, with regard to their potential use as probiotics.
- MeSH
- Bifidobacterium classification isolation & purification physiology MeSH
- Poultry MeSH
- Gastrointestinal Tract microbiology MeSH
- Insecta MeSH
- Humans MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Comparative Study MeSH
Animal products are one of the niches of bifidobacteria, a fact probably attributable to secondary contamination. In this study, 2 species of the genus Bifidobacterium were isolated by culture-dependent methods from ovine cheeses that were made from unpasteurized milk without addition of starter cultures. The isolates were identified as Bifidobacterium crudilactis and Bifidobacterium animalis subsp. lactis using matrix-assisted laser desorption/ionization time-of-flight analysis and sequencing of phylogenetic markers (16S rRNA, hsp60, and fusA).
- MeSH
- Bifidobacterium classification genetics isolation & purification MeSH
- Phylogeny * MeSH
- Milk microbiology MeSH
- Molecular Sequence Data MeSH
- Sheep, Domestic MeSH
- Food Microbiology * MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Cheese microbiology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The taxonomic position of Bifidobacterium stercoris Eg1(T) ( = JCM 15918(T)) based on comparative 16S rRNA gene and hsp60 sequence analyses was found to be controversial, as the strain showed high similarity to the type strain of Bifidobacterium adolescentis, CCUG 18363(T). Therefore, the relationship between the two species was investigated by a taxonomic study that included, in addition to re-evaluation of the 16S rRNA gene sequence, determination of DNA-DNA binding and multilocus sequence analysis (MLSA) of housekeeping genes encoding the DNA-directed RNA polymerase B subunit (rpoC), putative xylulose-5-phosphate/fructose-6-phosphate phosphoketolase (xfp), elongation factor EF-G (fusA), 50S ribosomal protein L2 (rplB) and DNA gyrase B subunit (gyrB). Comparative 16S rRNA gene sequence analysis showed relatively high similarity (98.9 %) between B. stercoris KCTC 5756(T) and B. adolescentis ATCC 15703(T). MLSA revealed close relatedness between B. stercoris KCTC 5756(T) and B. adolescentis CCUG 18363(T), with 99.3-100 % similarity between the rpoC, xfp, fusA, rplB and gyrB gene sequences. In addition, relatively high dnaJ1 gene sequence similarity of 97.7 % was found between the strains. Similar phenotypes and a high DNA-DNA binding value (78.9 %) confirmed that B. stercoris and B. adolescentis are synonymous. Based on these results, it is proposed that the species Bifidobacterium stercoris Kim et al. 2010 should be reclassified as a later heterotypic synonym of Bifidobacterium adolescentis Reuter 1963 (Approved Lists 1980).
- MeSH
- Aldehyde-Lyases genetics MeSH
- Bifidobacterium classification genetics MeSH
- DNA, Bacterial genetics MeSH
- DNA Gyrase genetics MeSH
- DNA-Directed RNA Polymerases genetics MeSH
- Peptide Elongation Factor G genetics MeSH
- Phenotype MeSH
- Phylogeny * MeSH
- Nucleic Acid Hybridization MeSH
- Molecular Sequence Data MeSH
- Multilocus Sequence Typing MeSH
- Ribosomal Proteins genetics MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Sequence Analysis, DNA MeSH
- Bacterial Typing Techniques MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
