The Experts below are selected from a list of 1518 Experts worldwide ranked by ideXlab platform

Jiří Killer - One of the best experts on this subject based on the ideXlab platform.

  • Genetic marker-based multi-locus sequence analysis for classification, genotyping, and phylogenetics of the family Bifidobacteriaceae as an alternative approach to phylogenomics.
    Antonie van Leeuwenhoek, 2019
    Co-Authors: Chahrazed Mekadim, Věra Bunesova, Eva Vlková, Zuzana Hroncová, Jiří Killer
    Abstract:

    Bifidobacteria are widely known for their probiotic potential; however, little is known regarding the ecological significance and potential probiotic effects of the phylogenetically related ‘scardovial’ genera (Aeriscardovia, Alloscardovia, Bombiscardovia, Galliscardovia, Neoscardovia, Parascardovia, Pseudoscardovia and Scardovia) and Gardnerella classified with bifidobacteria within the Bifidobacteriaceae family. Accurate classification and genotyping of bacteria using certain housekeeping genes is possible, whilst current phylogenomic analyses allow for extremely precise classification. Studies of applicable genetic markers may provide results comparable to those obtained from phylogenomic analyses of the family Bifidobacteriaceae. Segments of the glyS (624 nucleotides), pheS (555 nucleotides), rpsA (630 nucleotides), and rpsB (432 nucleotides) genes and their concatenated sequence were explored. The mean glyS, pheS, rpsB and rpsA gene sequence similarities calculated for Bifidobacterium taxa were 84.8, 85.2, 90.2 and 86.8%, respectively. Interestingly, the average value of the Average Nucleotide Identity among 67 type strains of the family Bifidobacteriaceae (84.70%) calculated based on values published recently was in agreement with the average pairwise similarity (84.6%) among 75 type strains of Bifidobacteriaceae family computed in this study using the concatenated sequences of four gene fragments. Similar to phylogenomic analyses, several gene sequence and phylogenetic analyses revealed that concatenated gene regions allow for classification of Bifidobacteriaceae strains into particular phylogenetic clusters and groups. Phylogeny reconstructed from the concatenated sequences assisted in defining two novel phylogenetic groups, the Bifidobacterium psychraerophilum group consisting of B. psychraerophilum, Bifidobacterium crudilactis and Bifidobacterium aquikefiri species and the Bifidobacterium bombi group consisting of B. bombi, Bifidobacterium bohemicum and Bifidobacterium commune.

  • Glutamine synthetase type I (glnAI) represents a rewarding molecular marker in the classification of bifidobacteria and related genera.
    Folia microbiologica, 2019
    Co-Authors: Jiří Killer, Chahrazed Mekadim, Věra Bunesova, Jakub Mrázek, Zuzana Hroncová, Eva Vlková
    Abstract:

    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.

  • gene encoding the ctp synthetase as an appropriate molecular tool for identification and phylogenetic study of the family Bifidobacteriaceae
    MicrobiologyOpen, 2018
    Co-Authors: Jiří Killer, Chahrazed Mekadim, Radko Pechar, Věra Bunesova, Jan Mrazek, Eva Vlková
    Abstract:

    : An alternative molecular marker with respect to the 16S rRNA gene demonstrating better identification and phylogenetic parameters has not been designed for the whole Bifidobacteriaceae family, which includes the genus Bifidobacterium and scardovial genera. Therefore, the aim of the study was to find such a gene in available genomic sequences, suggest appropriate means and conditions for asmplification and sequencing of the desired region of the selected gene in various strains of the bacterial family and verify the importance in classification and phylogeny. Specific primers flanking the variable region (~800 pb) within the pyrG gene encoding the CTP synthetase were designed by means of gene sequences retrieved from the genomes of strains belonging to the family Bifidobacteriaceae. The functionality and specificity of the primers were subsequently tested on the wild (7) and type strains of bifidobacteria (36) and scardovia (7). Comparative and phylogenetic studies based on obtained sequences revealed actual significance in classification and phylogeny of the Bifidobacteriaceae family. Gene statistics (percentages of mean sequence similarities and identical sites, mean number of nucleotide differences, P- and K-distances) and phylogenetic analyses (congruence between tree topologies, percentages of bootstrap values >50 and 70%) indicate that the pyrG gene represents an alternative identification and phylogenetic marker exhibiting higher discriminatory power among strains, (sub)species, and genera than the 16S rRNA gene. Sequences of the particular gene fragment, simply achieved through specific primers, enable more precisely to classify and evaluate phylogeny of the family Bifidobacteriaceae including, with some exceptions, health-promoting probiotic bacteria.

  • Galliscardovia ingluviei gen. nov., sp. nov., a thermophilic bacterium of the family Bifidobacteriaceae isolated from the crop of a laying hen (Gallus gallus f. domestica).
    International journal of systematic and evolutionary microbiology, 2017
    Co-Authors: Radko Pechar, Věra Bunesova, Jiří Killer, Roman Svejstil, Hana Salmonová, Martina Geigerová, Vojtech Rada, Oldřich Benada
    Abstract:

    Bacteria with potential probiotic applications are not yet sufficiently explored, even for animals with economic importance. Therefore, we decided to isolate and identify representatives of the family Bifidobacteriaceae , which inhabit the crop of laying hens. During the study, a fructose-6-phosphate phosphoketolase-positive strain, RP51T, with a regular/slightly irregular and sometimes an S-shaped slightly curved rod-like shape, was isolated from the crop of a 13 -month-old Hisex Brown hybrid laying hen. The best growth of the Gram-stain-positive bacterium, which was isolated using Bifidobacterium -selective mTPY agar, was found out to be under strictly anaerobic conditions, however an ability to grow under microaerophilic and aerobic conditions was also observed. Sequencing of the almost complete 16S rRNA gene (1444 bp) showed Alloscardovia omnicolens CCUG 31649T and Bombiscardovia coagulans BLAPIII/AGVT to be the most closely related species with similarities of 93.4 and 93.1 %, respectively. Lower sequence similarities were determined with other scardovial genera and other representatives of the genus Bifidobacterium . Taxonomic relationships with A. omnicolens and other members of the family Bifidobacteriaceae were also demonstrated, based on the sequences of dnaK, fusA, hsp60 and rplB gene fragments. Low sequence similarities of phylogenetic markers to related scardovial genera and bifidobacteria along with unique features of the bacterial strain investigated within the family Bifidobacteriaceae ( including the lowest DNA G+C value (44.3 mol%), a unique spectrum of cellular fatty acids and polar lipids, cellular morphology, the wide temperature range for growth (15–49 °C) and habitat) clearly indicate that strain RP51T is a representative of a novel genus within the family Bifidobacteriaceae for which the name Galliscardovia ingluviei gen. nov., sp. nov. (RP51T=DSM 100235T=LMG 28778T=CCM 8606T) is proposed.

  • Pseudoscardovia radai sp. nov., a representative of the family Bifidobacteriaceae isolated from the digestive tract of a wild pig (Sus scrofa scrofa)
    International Journal of Systematic and Evolutionary Microbiology, 2014
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jaroslav Havlik, O Benada
    Abstract:

    The presence of bifidobacteria and representatives of the new genus Pseudoscardovia within the family Bifidobacteriaceae in the digestive tract of wild pigs was reported recently. Results based on comparative 16S rRNA gene sequence analysis of a new fructose-6-phosphate phosphoketolase-positive bacterial isolate, strain DPVI-TET3T, originating from the small intestine of a wild pig revealed a relationship to Pseudoscardovia suis DPTE4T (96.8 % sequence similarity). Phylogenetic and comparative analyses based on 16S rRNA, hsp60, xfp, fusA, tuf and rpoC partial gene sequences confirmed the relationship of the novel bacterial strain to P. suis DPTE4T in comparison with other bifidobacterial species occurring in the digestive tract of domestic and wild pigs. Differences in utilization of various substrates, production of enzymes, cell morphology, peptidoglycan structure and profiles of cellular fatty acids and polar lipids between strain DPVI-TET3T and P. suis DPTE4T allow the establishment of a novel species, for which the name Pseudoscardovia radai sp. nov. is proposed. The type strain is strain DPVI-TET3T ( = CCM 7943T = DSM 24742T).

Paola Mattarelli - One of the best experts on this subject based on the ideXlab platform.

  • NON-HUMAN PRIMATES Bifidobacteriaceae: A RESERVOIR FOR APPLICATION FOR ANIMAL WELL-BEING
    2019
    Co-Authors: Monica Modesto, Piero Sciavilla, Donatella Scarafile, Beatrice Evangelisti, Caterina Spiezio, Camillo Sandri, Paola Mattarelli
    Abstract:

    After discover of bifidobacteria in human infant from H. Tissier in 1900, Bifidobacteriaceae microorganisms have been extensively studied mostly in the gastrointestinal tracts of human and other animals both from ecological and practical application point of view. Their importance is mainly related to their strict link with human and animal health due to many probiotic features such as modulation of immune system, antagonistic activity towards pathogens, alleviation of lactose intolerance, production of useful metabolites. Recently the BoCC-BUSCoB (Bologna Culture Collection - Bologna University Scardovi Collection of Bifidobacteria) has extensively studied the presence of bifidobacteria in non-human primates. Bifidobacteriaceae new species have been isolated from old world monkeys (Lemur catta and Eulemuris macaco), new world monkeys (Callithrix jacchus, Saguinus oedipus, Saguinus imperator, Terophitecus gelada) and hominidis (orangutan and chimpanzee). The study of non-human primates “probiotic microbiota”, where bifidobacteria represent one of the most important probiotic group, is very important especially in the view of their application for the well-being of animals in controlled environment. The exploitation of probiotic properties of strains isolated from non-human primates requires the existence of isolates in culture collections, which assure the maintenance with appropriate methodologies of bifidobacterial cultures for intended health and biotechnological uses

  • related genera within the family Bifidobacteriaceae
    The Bifidobacteria and Related Organisms#R##N#Biology Taxonomy Applications, 2018
    Co-Authors: Bruno Biavati, Paola Mattarelli
    Abstract:

    Abstract There are currently eight other genera (Alloscardovia, Aeriscardovia, Bombiscardovia, Gardnerella, Neoscardovia, Parascardovia, Pseudoscardovia, and Scardovia) identified on the basis of the usual polyphasic taxonomic approach belonging to the same “family” as Bifidobacterium. This chapter highlights the characteristics of the seven new taxa belonging to the so-called scardovial genera, describing the features of genus and species. In most cases both biodiversity and practical importance are largely unknown. The growing attention devoted to the genus Bifidobacterium is mainly connected to its role as a probiotic bacterium. Scardovial genera considered closely related to bifidobacteria have potentiality for applications as beneficial bacteria. The chapter also includes a short remembrance of Professor Vittorio Scardovi as a sign of recognition for the great scientific importance of his work.

  • chemotaxonomic features in the Bifidobacteriaceae family
    The Bifidobacteria and Related Organisms#R##N#Biology Taxonomy Applications, 2018
    Co-Authors: Paola Mattarelli, Barbara Sgorbati
    Abstract:

    Abstract Microbial chemistry has been extremely important in identifying many major structural components of microorganisms. Chemotaxonomy (1) describes the natural variability between bacterial species of many monomers present in structural macromolecules (e.g., cellular fatty acids, peptidoglycan structure, etc.); (2) helps in understanding the functional role of many of these structural compounds on the physiology of the bacterial cells; and (3) provides chemical markers useful in taxonomy. This chapter deals with the importance of chemotaxonomy in the framework of the polyphasic taxonomic approach: in particular, aspects of classification, degree of correlation, and aspects of evolution based on chemotaxonomic markers in the Bifidobacteriaceae family are considered.

  • Comparative genomic and phylogenomic analyses of the Bifidobacteriaceae family
    BMC genomics, 2017
    Co-Authors: Gabriele Andrea Lugli, Paola Mattarelli, Christian Milani, Francesca Turroni, Sabrina Duranti, Leonardo Mancabelli, Marta Mangifesta, Chiara Ferrario, Monica Modesto, Killer Jiří
    Abstract:

    Members of the Bifidobacteriaceae family represent both dominant microbial groups that colonize the gut of various animals, especially during the suckling stage of their life, while they also occur as pathogenic bacteria of the urogenital tract. The pan-genome of the genus Bifidobacterium has been explored in detail in recent years, though genomics of the Bifidobacteriaceae family has not yet received much attention. Here, a comparative genomic analyses of 67 Bifidobacteriaceae (sub) species including all currently recognized genera of this family, i.e., Aeriscardovia, Alloscardovia, Bifidobacterium, Bombiscardovia, Gardnerella, Neoscardovia, Parascardovia, Pseudoscardovia and Scardovia, was performed. Furthermore, in order to include a representative of each of the 67 (currently recognized) (sub) species belonging to the Bifidobacteriaceae family, we sequenced the genomes of an additional 11 species from this family, accomplishing the most extensive comparative genomic analysis performed within this family so far. Phylogenomics-based analyses revealed the deduced evolutionary pathway followed by each member of the Bifidobacteriaceae family, highlighting Aeriscardovia aeriphila LMG 21773 as the deepest branch in the evolutionary tree of this family. Furthermore, functional analyses based on genome content unveil connections between a given member of the family, its carbohydrate utilization abilities and its corresponding host. In this context, bifidobacterial (sub) species isolated from humans and monkeys possess the highest relative number of acquired glycosyl hydrolase-encoding genes, probably in order to enhance their metabolic ability to utilize different carbon sources consumed by the host. Within the Bifidobacteriaceae family, genomics of the genus Bifidobacterium has been extensively investigated. In contrast, very little is known about the genomics of members of the other eight genera of this family. In this study, we decoded the genome sequences of each member of the Bifidobacteriaceae family. Thanks to subsequent comparative genomic and phylogenetic analyses, the deduced pan-genome of this family, as well as the predicted evolutionary development of each taxon belonging to this family was assessed.

  • Additional file 2: Figure S1. of Comparative genomic and phylogenomic analyses of the Bifidobacteriaceae family
    2017
    Co-Authors: Gabriele Lugli, Paola Mattarelli, Christian Milani, Francesca Turroni, Sabrina Duranti, Leonardo Mancabelli, Marta Mangifesta, Chiara Ferrario, Monica Modesto, Killer Jiří
    Abstract:

    Phylogenetic trees of the Bifidobacteriaceae family. Panel a display the 16S rRNA gene-based tree of the current recognized (sub) species of the family. Panel b shows the phylogenetic tree based on the concatenation of the amino acid sequences of five housekeeping genes including hsp60, rpoB, dnaJ, dnaG and clpC. For each tree, bootstrap values higher than 70 are marked near the respective nodes. (TIFF 2260 kb

Eva Vlková - One of the best experts on this subject based on the ideXlab platform.

  • Genetic marker-based multi-locus sequence analysis for classification, genotyping, and phylogenetics of the family Bifidobacteriaceae as an alternative approach to phylogenomics.
    Antonie van Leeuwenhoek, 2019
    Co-Authors: Chahrazed Mekadim, Věra Bunesova, Eva Vlková, Zuzana Hroncová, Jiří Killer
    Abstract:

    Bifidobacteria are widely known for their probiotic potential; however, little is known regarding the ecological significance and potential probiotic effects of the phylogenetically related ‘scardovial’ genera (Aeriscardovia, Alloscardovia, Bombiscardovia, Galliscardovia, Neoscardovia, Parascardovia, Pseudoscardovia and Scardovia) and Gardnerella classified with bifidobacteria within the Bifidobacteriaceae family. Accurate classification and genotyping of bacteria using certain housekeeping genes is possible, whilst current phylogenomic analyses allow for extremely precise classification. Studies of applicable genetic markers may provide results comparable to those obtained from phylogenomic analyses of the family Bifidobacteriaceae. Segments of the glyS (624 nucleotides), pheS (555 nucleotides), rpsA (630 nucleotides), and rpsB (432 nucleotides) genes and their concatenated sequence were explored. The mean glyS, pheS, rpsB and rpsA gene sequence similarities calculated for Bifidobacterium taxa were 84.8, 85.2, 90.2 and 86.8%, respectively. Interestingly, the average value of the Average Nucleotide Identity among 67 type strains of the family Bifidobacteriaceae (84.70%) calculated based on values published recently was in agreement with the average pairwise similarity (84.6%) among 75 type strains of Bifidobacteriaceae family computed in this study using the concatenated sequences of four gene fragments. Similar to phylogenomic analyses, several gene sequence and phylogenetic analyses revealed that concatenated gene regions allow for classification of Bifidobacteriaceae strains into particular phylogenetic clusters and groups. Phylogeny reconstructed from the concatenated sequences assisted in defining two novel phylogenetic groups, the Bifidobacterium psychraerophilum group consisting of B. psychraerophilum, Bifidobacterium crudilactis and Bifidobacterium aquikefiri species and the Bifidobacterium bombi group consisting of B. bombi, Bifidobacterium bohemicum and Bifidobacterium commune.

  • Glutamine synthetase type I (glnAI) represents a rewarding molecular marker in the classification of bifidobacteria and related genera.
    Folia microbiologica, 2019
    Co-Authors: Jiří Killer, Chahrazed Mekadim, Věra Bunesova, Jakub Mrázek, Zuzana Hroncová, Eva Vlková
    Abstract:

    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.

  • gene encoding the ctp synthetase as an appropriate molecular tool for identification and phylogenetic study of the family Bifidobacteriaceae
    MicrobiologyOpen, 2018
    Co-Authors: Jiří Killer, Chahrazed Mekadim, Radko Pechar, Věra Bunesova, Jan Mrazek, Eva Vlková
    Abstract:

    : An alternative molecular marker with respect to the 16S rRNA gene demonstrating better identification and phylogenetic parameters has not been designed for the whole Bifidobacteriaceae family, which includes the genus Bifidobacterium and scardovial genera. Therefore, the aim of the study was to find such a gene in available genomic sequences, suggest appropriate means and conditions for asmplification and sequencing of the desired region of the selected gene in various strains of the bacterial family and verify the importance in classification and phylogeny. Specific primers flanking the variable region (~800 pb) within the pyrG gene encoding the CTP synthetase were designed by means of gene sequences retrieved from the genomes of strains belonging to the family Bifidobacteriaceae. The functionality and specificity of the primers were subsequently tested on the wild (7) and type strains of bifidobacteria (36) and scardovia (7). Comparative and phylogenetic studies based on obtained sequences revealed actual significance in classification and phylogeny of the Bifidobacteriaceae family. Gene statistics (percentages of mean sequence similarities and identical sites, mean number of nucleotide differences, P- and K-distances) and phylogenetic analyses (congruence between tree topologies, percentages of bootstrap values >50 and 70%) indicate that the pyrG gene represents an alternative identification and phylogenetic marker exhibiting higher discriminatory power among strains, (sub)species, and genera than the 16S rRNA gene. Sequences of the particular gene fragment, simply achieved through specific primers, enable more precisely to classify and evaluate phylogeny of the family Bifidobacteriaceae including, with some exceptions, health-promoting probiotic bacteria.

  • Pseudoscardovia radai sp. nov., a representative of the family Bifidobacteriaceae isolated from the digestive tract of a wild pig (Sus scrofa scrofa)
    International Journal of Systematic and Evolutionary Microbiology, 2014
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jaroslav Havlik, O Benada
    Abstract:

    The presence of bifidobacteria and representatives of the new genus Pseudoscardovia within the family Bifidobacteriaceae in the digestive tract of wild pigs was reported recently. Results based on comparative 16S rRNA gene sequence analysis of a new fructose-6-phosphate phosphoketolase-positive bacterial isolate, strain DPVI-TET3T, originating from the small intestine of a wild pig revealed a relationship to Pseudoscardovia suis DPTE4T (96.8 % sequence similarity). Phylogenetic and comparative analyses based on 16S rRNA, hsp60, xfp, fusA, tuf and rpoC partial gene sequences confirmed the relationship of the novel bacterial strain to P. suis DPTE4T in comparison with other bifidobacterial species occurring in the digestive tract of domestic and wild pigs. Differences in utilization of various substrates, production of enzymes, cell morphology, peptidoglycan structure and profiles of cellular fatty acids and polar lipids between strain DPVI-TET3T and P. suis DPTE4T allow the establishment of a novel species, for which the name Pseudoscardovia radai sp. nov. is proposed. The type strain is strain DPVI-TET3T ( = CCM 7943T = DSM 24742T).

  • Pseudoscardovia radai sp. nov., a representative of the family Bifidobacteriaceae isolated from the digestive tract of a wild pig (Sus scrofa scrofa)
    International journal of systematic and evolutionary microbiology, 2014
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jaroslav Havlik, Oldrich Benada
    Abstract:

    Presence of bifidobacteria and representatives of the new genus Pseudoscardovia within the family Bifidobacteriaceae in the digestive tract of wild pigs has been reported recently. Results based on comparative 16S rRNA gene sequence analysis of a new fructose-6-phosphate phosphoketolase-positive bacterial isolate originated from the small intestine of a wild pig revealed a relationship to Pseudoscardovia suis DPTE4T (96.8% sequence similarity). Phylogenetic and comparative analyses based on 16S rRNA, hsp60, xfp, fusA, tuf and rpoC partial gene sequences confirmed relationship of the new bacterial strain to Pseudoscardovia suis compared with bifidobacteria species occurring in the digestive tract of domestic and wild pigs. Differences in utilization of various substrates, production of enzymes, cell morphology, peptidoglycan structure, profile of cellular fatty acids and polar lipids between the new bacterial isolate designated as DPVI-TET3T and P. suis DPTE4T allow to establish a new bacterial taxon for which the name Pseudoscardovia radai sp. nov. (= DPVI/TET3T = CCM 7943T = DSM 24742T) was proposed.

Věra Bunesova - One of the best experts on this subject based on the ideXlab platform.

  • Genetic marker-based multi-locus sequence analysis for classification, genotyping, and phylogenetics of the family Bifidobacteriaceae as an alternative approach to phylogenomics.
    Antonie van Leeuwenhoek, 2019
    Co-Authors: Chahrazed Mekadim, Věra Bunesova, Eva Vlková, Zuzana Hroncová, Jiří Killer
    Abstract:

    Bifidobacteria are widely known for their probiotic potential; however, little is known regarding the ecological significance and potential probiotic effects of the phylogenetically related ‘scardovial’ genera (Aeriscardovia, Alloscardovia, Bombiscardovia, Galliscardovia, Neoscardovia, Parascardovia, Pseudoscardovia and Scardovia) and Gardnerella classified with bifidobacteria within the Bifidobacteriaceae family. Accurate classification and genotyping of bacteria using certain housekeeping genes is possible, whilst current phylogenomic analyses allow for extremely precise classification. Studies of applicable genetic markers may provide results comparable to those obtained from phylogenomic analyses of the family Bifidobacteriaceae. Segments of the glyS (624 nucleotides), pheS (555 nucleotides), rpsA (630 nucleotides), and rpsB (432 nucleotides) genes and their concatenated sequence were explored. The mean glyS, pheS, rpsB and rpsA gene sequence similarities calculated for Bifidobacterium taxa were 84.8, 85.2, 90.2 and 86.8%, respectively. Interestingly, the average value of the Average Nucleotide Identity among 67 type strains of the family Bifidobacteriaceae (84.70%) calculated based on values published recently was in agreement with the average pairwise similarity (84.6%) among 75 type strains of Bifidobacteriaceae family computed in this study using the concatenated sequences of four gene fragments. Similar to phylogenomic analyses, several gene sequence and phylogenetic analyses revealed that concatenated gene regions allow for classification of Bifidobacteriaceae strains into particular phylogenetic clusters and groups. Phylogeny reconstructed from the concatenated sequences assisted in defining two novel phylogenetic groups, the Bifidobacterium psychraerophilum group consisting of B. psychraerophilum, Bifidobacterium crudilactis and Bifidobacterium aquikefiri species and the Bifidobacterium bombi group consisting of B. bombi, Bifidobacterium bohemicum and Bifidobacterium commune.

  • Glutamine synthetase type I (glnAI) represents a rewarding molecular marker in the classification of bifidobacteria and related genera.
    Folia microbiologica, 2019
    Co-Authors: Jiří Killer, Chahrazed Mekadim, Věra Bunesova, Jakub Mrázek, Zuzana Hroncová, Eva Vlková
    Abstract:

    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.

  • gene encoding the ctp synthetase as an appropriate molecular tool for identification and phylogenetic study of the family Bifidobacteriaceae
    MicrobiologyOpen, 2018
    Co-Authors: Jiří Killer, Chahrazed Mekadim, Radko Pechar, Věra Bunesova, Jan Mrazek, Eva Vlková
    Abstract:

    : An alternative molecular marker with respect to the 16S rRNA gene demonstrating better identification and phylogenetic parameters has not been designed for the whole Bifidobacteriaceae family, which includes the genus Bifidobacterium and scardovial genera. Therefore, the aim of the study was to find such a gene in available genomic sequences, suggest appropriate means and conditions for asmplification and sequencing of the desired region of the selected gene in various strains of the bacterial family and verify the importance in classification and phylogeny. Specific primers flanking the variable region (~800 pb) within the pyrG gene encoding the CTP synthetase were designed by means of gene sequences retrieved from the genomes of strains belonging to the family Bifidobacteriaceae. The functionality and specificity of the primers were subsequently tested on the wild (7) and type strains of bifidobacteria (36) and scardovia (7). Comparative and phylogenetic studies based on obtained sequences revealed actual significance in classification and phylogeny of the Bifidobacteriaceae family. Gene statistics (percentages of mean sequence similarities and identical sites, mean number of nucleotide differences, P- and K-distances) and phylogenetic analyses (congruence between tree topologies, percentages of bootstrap values >50 and 70%) indicate that the pyrG gene represents an alternative identification and phylogenetic marker exhibiting higher discriminatory power among strains, (sub)species, and genera than the 16S rRNA gene. Sequences of the particular gene fragment, simply achieved through specific primers, enable more precisely to classify and evaluate phylogeny of the family Bifidobacteriaceae including, with some exceptions, health-promoting probiotic bacteria.

  • Galliscardovia ingluviei gen. nov., sp. nov., a thermophilic bacterium of the family Bifidobacteriaceae isolated from the crop of a laying hen (Gallus gallus f. domestica).
    International journal of systematic and evolutionary microbiology, 2017
    Co-Authors: Radko Pechar, Věra Bunesova, Jiří Killer, Roman Svejstil, Hana Salmonová, Martina Geigerová, Vojtech Rada, Oldřich Benada
    Abstract:

    Bacteria with potential probiotic applications are not yet sufficiently explored, even for animals with economic importance. Therefore, we decided to isolate and identify representatives of the family Bifidobacteriaceae , which inhabit the crop of laying hens. During the study, a fructose-6-phosphate phosphoketolase-positive strain, RP51T, with a regular/slightly irregular and sometimes an S-shaped slightly curved rod-like shape, was isolated from the crop of a 13 -month-old Hisex Brown hybrid laying hen. The best growth of the Gram-stain-positive bacterium, which was isolated using Bifidobacterium -selective mTPY agar, was found out to be under strictly anaerobic conditions, however an ability to grow under microaerophilic and aerobic conditions was also observed. Sequencing of the almost complete 16S rRNA gene (1444 bp) showed Alloscardovia omnicolens CCUG 31649T and Bombiscardovia coagulans BLAPIII/AGVT to be the most closely related species with similarities of 93.4 and 93.1 %, respectively. Lower sequence similarities were determined with other scardovial genera and other representatives of the genus Bifidobacterium . Taxonomic relationships with A. omnicolens and other members of the family Bifidobacteriaceae were also demonstrated, based on the sequences of dnaK, fusA, hsp60 and rplB gene fragments. Low sequence similarities of phylogenetic markers to related scardovial genera and bifidobacteria along with unique features of the bacterial strain investigated within the family Bifidobacteriaceae ( including the lowest DNA G+C value (44.3 mol%), a unique spectrum of cellular fatty acids and polar lipids, cellular morphology, the wide temperature range for growth (15–49 °C) and habitat) clearly indicate that strain RP51T is a representative of a novel genus within the family Bifidobacteriaceae for which the name Galliscardovia ingluviei gen. nov., sp. nov. (RP51T=DSM 100235T=LMG 28778T=CCM 8606T) is proposed.

  • Pseudoscardovia radai sp. nov., a representative of the family Bifidobacteriaceae isolated from the digestive tract of a wild pig (Sus scrofa scrofa)
    International Journal of Systematic and Evolutionary Microbiology, 2014
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jaroslav Havlik, O Benada
    Abstract:

    The presence of bifidobacteria and representatives of the new genus Pseudoscardovia within the family Bifidobacteriaceae in the digestive tract of wild pigs was reported recently. Results based on comparative 16S rRNA gene sequence analysis of a new fructose-6-phosphate phosphoketolase-positive bacterial isolate, strain DPVI-TET3T, originating from the small intestine of a wild pig revealed a relationship to Pseudoscardovia suis DPTE4T (96.8 % sequence similarity). Phylogenetic and comparative analyses based on 16S rRNA, hsp60, xfp, fusA, tuf and rpoC partial gene sequences confirmed the relationship of the novel bacterial strain to P. suis DPTE4T in comparison with other bifidobacterial species occurring in the digestive tract of domestic and wild pigs. Differences in utilization of various substrates, production of enzymes, cell morphology, peptidoglycan structure and profiles of cellular fatty acids and polar lipids between strain DPVI-TET3T and P. suis DPTE4T allow the establishment of a novel species, for which the name Pseudoscardovia radai sp. nov. is proposed. The type strain is strain DPVI-TET3T ( = CCM 7943T = DSM 24742T).

Jaroslav Havlik - One of the best experts on this subject based on the ideXlab platform.

  • Pseudoscardovia radai sp. nov., a representative of the family Bifidobacteriaceae isolated from the digestive tract of a wild pig (Sus scrofa scrofa)
    International Journal of Systematic and Evolutionary Microbiology, 2014
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jaroslav Havlik, O Benada
    Abstract:

    The presence of bifidobacteria and representatives of the new genus Pseudoscardovia within the family Bifidobacteriaceae in the digestive tract of wild pigs was reported recently. Results based on comparative 16S rRNA gene sequence analysis of a new fructose-6-phosphate phosphoketolase-positive bacterial isolate, strain DPVI-TET3T, originating from the small intestine of a wild pig revealed a relationship to Pseudoscardovia suis DPTE4T (96.8 % sequence similarity). Phylogenetic and comparative analyses based on 16S rRNA, hsp60, xfp, fusA, tuf and rpoC partial gene sequences confirmed the relationship of the novel bacterial strain to P. suis DPTE4T in comparison with other bifidobacterial species occurring in the digestive tract of domestic and wild pigs. Differences in utilization of various substrates, production of enzymes, cell morphology, peptidoglycan structure and profiles of cellular fatty acids and polar lipids between strain DPVI-TET3T and P. suis DPTE4T allow the establishment of a novel species, for which the name Pseudoscardovia radai sp. nov. is proposed. The type strain is strain DPVI-TET3T ( = CCM 7943T = DSM 24742T).

  • Pseudoscardovia radai sp. nov., a representative of the family Bifidobacteriaceae isolated from the digestive tract of a wild pig (Sus scrofa scrofa)
    International journal of systematic and evolutionary microbiology, 2014
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jaroslav Havlik, Oldrich Benada
    Abstract:

    Presence of bifidobacteria and representatives of the new genus Pseudoscardovia within the family Bifidobacteriaceae in the digestive tract of wild pigs has been reported recently. Results based on comparative 16S rRNA gene sequence analysis of a new fructose-6-phosphate phosphoketolase-positive bacterial isolate originated from the small intestine of a wild pig revealed a relationship to Pseudoscardovia suis DPTE4T (96.8% sequence similarity). Phylogenetic and comparative analyses based on 16S rRNA, hsp60, xfp, fusA, tuf and rpoC partial gene sequences confirmed relationship of the new bacterial strain to Pseudoscardovia suis compared with bifidobacteria species occurring in the digestive tract of domestic and wild pigs. Differences in utilization of various substrates, production of enzymes, cell morphology, peptidoglycan structure, profile of cellular fatty acids and polar lipids between the new bacterial isolate designated as DPVI-TET3T and P. suis DPTE4T allow to establish a new bacterial taxon for which the name Pseudoscardovia radai sp. nov. (= DPVI/TET3T = CCM 7943T = DSM 24742T) was proposed.

  • Alloscardovia macacae sp. nov., isolated from the milk of a macaque (Macaca mulatta), emended description of the genus Alloscardovia and proposal of Alloscardovia criceti comb. nov.
    International journal of systematic and evolutionary microbiology, 2013
    Co-Authors: Jiří Killer, Věra Bunesova, Eva Vlková, Jan Kopečný, Jaroslav Havlik, Olga Kofroňová, Š Ročková, V Rada, O Benada, Radko Pechar
    Abstract:

    A novel bacterial strain, designated M8(T), was isolated from milk of a female macaque bred in captivity. The strain was Gram-stain-positive, anaerobic, irregular coccoid-rod-shaped without catalase activity. Analysis of 16S rRNA gene sequence similarity revealed that the isolate was most closely related to Alloscardovia omnicolens CCUG 31649(T) (96.4%) and Metascardovia criceti OMB105(T) (96.6%). Sequences of hsp60, fusA, and xfp genes also confirmed that the strain was most closely related to the type strains of A. omnicolens and M. criceti. The isolate produced fructose-6-phosphate phosphoketolase which is in agreement with classification within the family Bifidobacteriaceae. The major fatty acids were C18 : 1ω9c (35.8%), C16 : 1 (6.2 %) and C14 : 0 (5.7 %). Polar lipid analysis revealed five different glycolipids, two unidentified phospholipids and diphosphatidylglycerol. The peptidoglycan was of the type A4α l-Lys-d-Asp with the presence of d(l)-alanine, d-glutamine, d-asparagine and l-lysine. The DNA G+C content of strain M8(T) was 50.1 mol%. On the basis of genetic, phylogenetic and phenotypic data, strain M8(T) represents a novel species of the genus Alloscardovia for which the name Alloscardovia macacae sp. nov. is proposed. The type strain is M8(T) ( = DSM 24762(T) = CCM 7944(T)). In addition, our results also revealed that Alloscardovia omnicolens DSM 21503(T) and Metascardovia criceti DSM 17774(T) do not belong to different genera within the family Bifidobacteriaceae. We therefore propose to reclassify Metascardovia criceti as Alloscardovia criceti comb. nov. An emended description of the genus Alloscardovia is also provided.

  • Bombiscardovia coagulans gen. nov., sp. nov., a new member of the family Bifidobacteriaceae isolated from the digestive tract of bumblebees
    Systematic and applied microbiology, 2010
    Co-Authors: Jiří Killer, Jan Kopečný, Jakub Mrázek, Vojtech Rada, Oldřich Benada, Jaroslav Havlik, I. Koppová, Olga Kofroňová
    Abstract:

    One hundred and eighty-seven fructose-6-phosphate phosphoketolase positive strains were isolated from the digestive tract of three different bumblebee species. Analyses of the partial 16S rRNA gene sequences of the representative strains showed only 92.8% and 92.5% similarity to Bifidobacterium coryneforme YIT 4092(T) and Bifidobacterium indicum JCM 1302(T), 92.2% similarity to Alloscardovia omnicolens CCUG 18650 and slightly reduced similarity of 91% to other members of the family Bifidobacteriaceae. On the other hand, analyses of the partial heat-shock protein 60 (hsp60) gene sequence revealed that the proposed type strain BLAPIII-AGV(T) was affiliated only to the 60 kDa chaperonin sequence of uncultured bacteria from human vagina (79-80%) and the hsp60 gene sequence of A. omnicolens CCUG 31649(T) (75.5%). The peptidoglycan type was A4α with an l-Lys-d-Asp interpeptide bridge. The polar lipids contained diphosphatidylglycerol, an unknown phospholipid, six glycolipids and two phosphoglycolipids. The major fatty acids were C(18:1), C(20:0) and C(18:0). These and other analyses indicated that the isolates represented a new genus within the family Bifidobacteriaceae. This observation was further substantiated by determination of the DNA G+C contents (46.1-47.1 mol%). Affinity of the strains to some scardovial genera (Aeriscardovia, Alloscardovia and Metascardovia) was also confirmed by their ability to grow under aerobic conditions. Besides the above mentioned differences, Bombiscardovia coagulans was found to differ from all scardovial genera in the ability to grow at temperatures as low as 5°C, which was another major phenotypically different characteristic of this new member of the family Bifidobacteriaceae. Hence, on the basis of phylogenetic analyses using partial 16S rRNA and hsp60 gene sequence data, and the temperature related phenotypic difference, we propose a novel taxa, B. coagulans gen. nov., sp. nov. (type strain=BLAPIII-AGV(T)=DSM 22924(T)=ATCC BAA-1568(T)).