Using probiotics represents a potential solution to post-weaning diarrheal diseases in piglets on commercial farms. The gastrointestinal tract of wild boars serves as a promising reservoir of novel lactic acid bacteria with suitable probiotic characteristics. In this study, we isolated eight bacterial strains from the intestinal content of wild boars identified as representatives of the species Bifidobacterium apri, Lactobacillus amylovorus, and Ligilactobacillus salivarius. These isolates underwent in vitro analysis and characterisation to assess their biological safety and probiotic properties. Analysis of their full genome sequences revealed the absence of horizontally transferrable genes for antibiotic resistance. However, seven out of eight isolates harboured genes encoding various types of bacteriocins in their genomes, and bacteriocin production was further confirmed by mass spectrometry analysis. Most of the tested strains demonstrated the ability to inhibit the growth of selected pathogenic bacteria, produce exopolysaccharides, and stimulate the expression of interleukin-10 in porcine macrophages. These characteristics deem the isolates characterised in this study as potential candidates for use as probiotics for piglets during the post-weaning period.

• Klíčová slova
• antibiotic susceptibility, antimicrobial activity, bacteriocins, exopolysaccharides, interleukin-10,
• Publikační typ
• časopisecké články MeSH

Probiotics are a potential strategy for salmonellosis control. A defined pig microbiota (DPM) mixture of nine bacterial strains previously exhibited probiotic and anti-Salmonella properties in vitro. Therefore, we evaluated its gut colonization ability and protection effect against S. typhimurium LT2-induced infection in the gnotobiotic piglet model. The DPM mixture successfully colonized the piglet gut and was stable and safe until the end of the experiment. The colon was inhabited by about 9 log CFU g-1 with a significant representation of bifidobacteria and lactobacilli compared to ileal levels around 7-8 log CFU g-1. Spore-forming clostridia and bacilli seemed to inhabit the environment only temporarily. The bacterial consortium contributed to the colonization of the gut at an entire length. The amplicon profile analysis supported the cultivation trend with a considerable representation of lactobacilli with bacilli in the ileum and bifidobacteria with clostridia in the colon. Although there was no significant Salmonella-positive elimination, it seems that the administered bacteria conferred the protection of infected piglets because of the slowed delayed infection manifestation without translocations of Salmonella cells to the blood circulation. Due to its colonization stability and potential protective anti-Salmonella traits, the DPM mixture has promising potential in pig production applications. However, advanced immunological tests are needed.

• Klíčová slova
• Salmonella typhimurium, bacilli, bacterial consortium, bifidobacteria, clostridia, lactobacilli,
• Publikační typ
• časopisecké články MeSH

Non-typhoidal Salmonella serovars are worldwide spread foodborne pathogens that cause diarrhea in humans and animals. Colonization of gnotobiotic piglet intestine with porcine indigenous mucinolytic Bifidobacterium boum RP36 strain and non-mucinolytic strain RP37 and their interference with Salmonella Typhimurium infection were compared. Bacterial interferences and impact on the host were evaluated by clinical signs of salmonellosis, bacterial translocation, goblet cell count, mRNA expression of mucin 2, villin, claudin-1, claudin-2, and occludin in the ileum and colon, and plasmatic levels of inflammatory cytokines IL-8, TNF-α, and IL-10. Both bifidobacterial strains colonized the intestine comparably. Neither RP36 nor RP37 B. boum strains effectively suppressed signs of salmonellosis. Both B. boum strains suppressed the growth of S. Typhimurium in the ileum and colon. The mucinolytic RP36 strain increased the translocation of S. Typhimurium into the blood, liver, and spleen.

• Klíčová slova
• Bifidobacterium boum, Salmonella Typhimurium, germ-free, gnotobiotic, goblet cells, mucin, mucinolytic, piglet,
• Publikační typ
• časopisecké články MeSH

Members of the Bifidobacterium dentium species are usually identified in the oral cavity of humans and associated with the development of plaque and dental caries. Nevertheless, they have also been detected from fecal samples, highlighting a widespread distribution among mammals. To explore the genetic variability of this species, we isolated and sequenced the genomes of 18 different B. dentium strains collected from fecal samples of several primate species and an Ursus arctos. Thus, we investigated the genomic variability and metabolic abilities of the new B. dentium isolates together with 20 public genome sequences. Comparative genomic analyses provided insights into the vast metabolic repertoire of the species, highlighting 19 glycosyl hydrolases families shared between each analyzed strain. Phylogenetic analysis of the B. dentium taxon, involving 1140 conserved genes, revealed a very close phylogenetic relatedness among members of this species. Furthermore, low genomic variability between strains was also confirmed by an average nucleotide identity analysis showing values higher than 98.2%. Investigating the genetic features of each strain, few putative functional mobile elements were identified. Besides, a consistent occurrence of defense mechanisms such as CRISPR-Cas and restriction-modification systems may be responsible for the high genome synteny identified among members of this taxon.

• Klíčová slova
• bifidobacteria, genomics, pangenome, phylogeny,
• Publikační typ
• časopisecké články MeSH

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
• bakteriální geny MeSH
• Bifidobacterium klasifikace   enzymologie   MeSH
• DNA bakterií genetika   MeSH
• DNA primery MeSH
• fylogeneze * MeSH
• genetické markery MeSH
• genotyp MeSH
• glutaminsynthetasa genetika   MeSH
• RNA ribozomální 16S genetika   MeSH
• sekvenční analýza DNA MeSH
• techniky typizace bakterií MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA bakterií MeSH
• DNA primery MeSH
• genetické markery MeSH
• glutamine synthetase I MeSH Prohlížeč
• glutaminsynthetasa MeSH
• RNA ribozomální 16S MeSH

The full biotechnological exploitation of thermostable enzymes in industrial processes is necessary for their commercial interest and industrious value. The heat-tolerant and heat-resistant enzymes are a key for efficient and cost-effective translation of substrates into useful products for commercial applications. The thermophilic, hyperthermophilic, and microorganisms adapted to extreme temperatures (i.e., low-temperature lovers or psychrophiles) are a rich source of thermostable enzymes with broad-ranging thermal properties, which have structural and functional stability to underpin a variety of technologies. These enzymes are under scrutiny for their great biotechnological potential. Temperature is one of the most critical parameters that shape microorganisms and their biomolecules for stability under harsh environmental conditions. This review describes in detail the sources of thermophiles and thermostable enzymes from prokaryotes and eukaryotes (microbial cell factories). Furthermore, the review critically examines perspectives to improve modern biocatalysts, its production and performance aiming to increase their value for biotechnology through higher standards, specificity, resistance, lowing costs, etc. These thermostable and thermally adapted extremophilic enzymes have been used in a wide range of industries that span all six enzyme classes. Thus, in particular, target of this review paper is to show the possibility of both high-value-low-volume (e.g., fine-chemical synthesis) and low-value-high-volume by-products (e.g., fuels) by minimizing changes to current industrial processes.

• MeSH
• Archaea enzymologie   metabolismus   MeSH
• Bacteria enzymologie   metabolismus   MeSH
• ekosystém MeSH
• enzymy MeSH
• nízká teplota * MeSH
• průmyslová mikrobiologie metody   MeSH
• stabilita enzymů MeSH
• vysoká teplota * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• enzymy 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.

• Klíčová slova
• Bifidobacterium, classification, genetic marker, phylogenetics, thrS gene,
• MeSH
• bakteriální geny MeSH
• bakteriální proteiny genetika   MeSH
• Bifidobacterium klasifikace   enzymologie   genetika   MeSH
• DNA bakterií genetika   MeSH
• fylogeneze * MeSH
• multilokusová sekvenční typizace MeSH
• ribozomální DNA genetika   MeSH
• RNA ribozomální 16S genetika   MeSH
• sekvenční analýza DNA MeSH
• techniky typizace bakterií MeSH
• threonin-tRNA-ligasa genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• DNA bakterií MeSH
• ribozomální DNA MeSH
• RNA ribozomální 16S MeSH
• threonin-tRNA-ligasa MeSH

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.

• Klíčová slova
• Bifidobacteriaceae, Bifidobacterium, CTP synthetase, classification, phylogenetics, scardovia,
• MeSH
• Actinobacteria klasifikace   enzymologie   genetika   izolace a purifikace   MeSH
• bakteriální proteiny chemie   genetika   metabolismus   MeSH
• DNA bakterií genetika   MeSH
• DNA primery genetika   MeSH
• fylogeneze * MeSH
• ligasy tvořící vazby C-N chemie   genetika   metabolismus   MeSH
• RNA ribozomální 16S genetika   MeSH
• techniky typizace bakterií metody   MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• CTP synthetase MeSH Prohlížeč
• DNA bakterií MeSH
• DNA primery MeSH
• ligasy tvořící vazby C-N MeSH
• RNA ribozomální 16S MeSH

Gram-stain-positive, catalase and oxidase-negative and short rod-shaped bacterium C10 with occasional branching was isolated under strictly anaerobic conditions from the rumen fluid of a red deer (Cervus elaphus) in the course of study attempting to uncover new xylanolytic and cellulolytic rumen bacteria inhabiting the digestive tract of wild ruminants in the Czech Republic. The anaerobic M10 medium containing bovine rumen fluid and carboxymethylcellulose as a defined source of organic carbon was used in the process of bacterial isolation. The 16S rRNA gene similarity revealed recently characterized new species Actinomyces succiniciruminis Am4T (GenBank accession number of the gene retrieved from the complete genome: LK995506) and Actinomyces glycerinitolerans G10T (GenBank accession number from the complete genome: NZFQTT01000017) as the closest relatives (99.7 and 99.6% gene pairwise identity, respectively), followed by the Actinomyces ruminicola DSM 27982T (97.2%, in all compared fragment of 41468 pb). Due to the taxonomic affinity of the examined strain to both species A. succiniciruminis and A. glycerinitolerans, its taxonomic status towards these species was evaluated using variable regions of rpsA (length of 519 bp) and rplB (597 bp) gene sequences amplified based on specific primers designed so as to be applicable in differentiation, classification, and phylogeny of Actinomyces species/strains. Comparative analyses using rpsA and rplB showed 98.5 and 97.9% similarities of C10 to A. succiniciruminis, respectively, and 97.5 and 97.6% similarities to A. glycerinitolerans, respectively. Thus, gene identities revealed that the evaluated isolate C10 (=DSM 100236 = LMG 28777) is a little more related to the species A. succiniciruminis isolated from the rumen of a Holstein-Friesian cow than A. glycerinitolerans. Phylogenetic analyses confirmed affinity of strain C10 to both recently characterized species. Unfortunately, they did not allow the bacterial strain to be classified into a particular species. Phenotypic characterization suggested similar conclusions. This brief contribution is aimed at classification and detailed phenotypic characterization of bacterial strain C10 isolated from the rumen of a wild red deer exhibiting, from the point of view of Actinomyces species, noteworthy cellulolytic and xylanolytic activities.

• MeSH
• Actinomyces klasifikace   genetika   izolace a purifikace   metabolismus   MeSH
• bachor mikrobiologie   MeSH
• bakteriální geny genetika   MeSH
• celulosa metabolismus   MeSH
• DNA bakterií genetika   MeSH
• fenotyp MeSH
• fylogeneze MeSH
• mastné kyseliny analýza   MeSH
• peptidoglykan analýza   MeSH
• RNA ribozomální 16S genetika   MeSH
• vysoká zvěř mikrobiologie   MeSH
• xylany metabolismus   MeSH
• zastoupení bazí MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• celulosa MeSH
• DNA bakterií MeSH
• mastné kyseliny MeSH
• peptidoglykan MeSH
• RNA ribozomální 16S MeSH
• xylany MeSH