Several species of eukaryotic organisms living in the high mountain areas of Armenia with naturally occurring levels of radiation have high adaptive responses to radiation. We speculate on the role ...of the gastrointestinal microbiota in this protection against radiation. Therefore, seventeen microorganisms with high antagonistic activities against several multi-drug-resistant pathogens were isolated from the human and animal gut microbiota, as well as from traditional Armenian fermented products. These strains were tested in vivo on Wistar rats to determine their ability to protect the eukaryotic host against radiation damages. The efficiency of the probiotics’ application and the dependence on pre- and post-radiation nutrition of rats were described. The effects of
Lactobacillus rhamnosus
Vahe, isolated from a healthy breastfed infant, and
Lactobacillus delbrueckii
IAHAHI, isolated from the fermented dairy product matsuni, on the survival of irradiated rats, and their blood leucocyte and glucose levels, were considered to be the most promising, based on this study’s results.
Summary
It was demonstrated recently that there is a system of general protein glycosylation in the human enteropathogen Campylobacter jejuni. To char‐ acterize such glycoproteins, we identified a ...lectin, Soybean agglutinin (SBA), which binds to multiple C. jejuni proteins on Western blots. Binding of lectin SBA was disrupted by mutagenesis of genes within the previously identified protein glycosylation locus. This lectin was used to purify putative glycoproteins selectively and, after sodium dodecyl sulphate‐ polyacrylamide gel electrophoresis (SDS–PAGE), Coomassie‐stained bands were cut from the gels. The bands were digested with trypsin, and peptides were identified by mass spectrometry and database searching. A 28 kDa band was identified as PEB3, a previously characterized immunogenic cell surface protein. Bands of 32 and 34 kDa were both identified as a putative periplasmic protein encoded by the C. jejuni NCTC 11168 coding sequence Cj1670c. We have named this putative glycoprotein CgpA. We constructed insertional knockout mutants of both the peb3 and cgpA genes, and surface protein extracts from mutant and wild‐type strains were analysed by one‐ and two‐dimensional polyacrylamide gel electrophoresis (PAGE). In this way, we were able to identify the PEB3 protein as a 28 kDa SBA‐reactive and immunoreactive glycoprotein. The cgpA gene encoded SBA‐reactive and immunoreactive proteins of 32 and 34 kDa. By using specific exoglycosidases, we demonstrated that the SBA binding property of acid‐glycine extractable C. jejuni glycoproteins, including PEB3 and CgpA, is a result of the presence of α‐linked N‐acetylgalactosamine residues. These data confirm the existence, and extend the boundaries, of the previously identified protein glycosylation locus of C. jejuni. Furthermore, we have identified two such glycoproteins, the first non‐flagellin campylobacter glycoproteins to be identified, and demonstrated that their glycan components contain α‐linked N‐acetylgalactosamine residues.
Whole genome sequences of four bacterial strains Dietzia maris SST1, Pseudomonas zhaodongensis SST2, Pseudomonas sp. SST3 and Halomonas sulfidaeris SST4, recovered from the South Shetland Trench ...sediment in Antarctica were analyzed using Ion Torrent sequencing technology. The respective sizes of their genomes (3.88, 4.99, 5.60 and 4.25 Mb) and GC contents (70.0, 60.3, 59.9 and 53.8%) are in agreement with these values of other strains of the species. The bacterial strains displayed promising antimicrobial activity against a number of pathogenic bacterial and fungal species. Whole genomes have been assembled and biosynthetic gene clusters (BGCs) have been identified using the antibiotics and Secondary Metabolite Analysis Shell (antiSMASH) web platform. Comparative analysis of the genome sequences revealed that the strains host abundant BGCs encoding for terpenes, siderophores, arylpolyene, bacteriocins, and lassopeptides. Furthermore, the key stress-related genes were identified and their distribution provided an insight into how these isolates adapt to key marine environmental conditions. This comprehensive study is a contribution to understanding the nature of life on the deep-sea environments.
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•The genomes of four bacterial strains from the South Shetland Trench were sequenced.•The genomes of the SST strains elicited BGCs of different classes of compounds.•Comparative metabolomics analyses revealed the high affinity of SST strains for new chemistry.•The genomes of SST strains contain a large number of genes involved in deep-sea adaptation.
This report describes the first draft genome sequence of a Corynebacterium pseudodiphtheriticum strain. The information on the genome organization and putative gene products will assist in better ...understanding of the molecular mechanisms involved in the beneficial probiotic effects of this bacterium.
Campylobacter jejuni is the leading cause of bacterial food-borne diarrhoeal disease throughout the world, and yet is still a poorly understood pathogen. Whole genome microarray comparisons of 11 C. ...jejuni strains of diverse origin identified genes in up to 30 NCTC 11168 loci ranging from 0.7 to 18.7 kb that are either absent or highly divergent in these isolates. Many of these regions are associated with the biosynthesis of surface structures including flagella, lipo-oligosaccharide, and the newly identified capsule. Other strain-variable genes of known function include those responsible for iron acquisition, DNA restriction/modification, and sialylation. In fact, at least 21% of genes in the sequenced strain appear dispensable as they are absent or highly divergent in one or more of the isolates tested, thus defining 1300 C. jejuni core genes. Such core genes contribute mainly to metabolic, biosynthetic, cellular, and regulatory processes, but many virulence determinants are also conserved. Comparison of the capsule biosynthesis locus revealed conservation of all the genes in this region in strains with the same Penner serotype as strain NCTC 11168. By contrast, between 5 and 17 NCTC 11168 genes in this region are either absent or highly divergent in strains of a different serotype from the sequenced strain, providing further evidence that the capsule accounts for Penner serotype specificity. These studies reveal extensive genetic diversity among C. jejuni strains and pave the way toward identifying correlates of pathogenicity and developing improved epidemiological tools for this problematic pathogen.
This report describes a draft genome sequence of Lactobacillus fermentum strain 3872. The data revealed remarkable similarity to and dissimilarity with the published genome sequences of other strains ...of the species. The absence of and variation in structures of some adhesins and the presence of an additional adhesin may reflect adaptation of the bacterium to different host systems and may contribute to specific properties of this strain as a new probiotic.
Unlike
,
is unable to import a range of sugars, including arabinose, which makes common expression vectors, such as pBAD33, non-functional in these bacteria.
The aim of this study was to investigate ...whether the
transporters AraE and modified LacY (LacYA177C) would enable
to uptake arabinose.
The respective genes of
were constitutively expressed in
strain 11168H after integration into the chromosome via homologous recombination. Vectors carrying these genes also contained a reporter gene,
, under the control of the arabinose-inducible promoter, pBAD. These constructs were verified in
by demonstrating the induction of
in the presence of arabinose. Integration of the genes into one of the rRNA gene clusters was verified by PCR and genome sequencing. The latter also confirmed that the inserted gene clusters contained no mutations. Expression of the
gene in the presence of arabinose inducer was monitored using fluorescence microscopy of colonies and fluorimetry using both whole cells and lysates.
The results demonstrated the inability of
to use arabinose transporters, which are fully functional in
, suggesting a remarkable difference in the physiology of these bacteria.
Here, we describe the draft sequence of a virulent isolate of Neisseria meningitidis strain L91543, belonging to serogroup C. The findings from previous proteomic and metabolomic studies of this ...strain can now be further interpreted with genomic analysis. Comparative analysis of the genome sequence revealed close similarity and localized synteny with the genome sequence of N. meningitidis serogroup C strain, FAM18. Polymorphisms were identified in the signal peptide sequence of factor H binding protein, a target for new meningococcal vaccines, which may result in its inefficient translocation across the cytoplasmic membrane affecting its processing (lipidation and cleavage of the signal peptide) and transportation to the outer membrane in strain L91543. This would explain the unusual proteomic data for factor H binding protein for this strain. NadA, another target for new vaccines, and the MtrR regulator, which controls expression of NadA, both contain SNPs between strains L91543 and FAM18. The genome sequence data were generated using Ion Torrent PGM sequencing, assembled into 50 contigs with 64× coverage and annotated with 2262 genes, 14 rRNAs and 56 tRNAs. The availability of the genome of N. meningitidis strain L91543 will aid our understanding of the proteome of this organism, importantly its vaccine antigens.
The draft genome sequence of Neisseria meningitidis serogroup C strain, L91543, reveals diversity at the genomic level in vaccine antigens and other features to complement previous proteomic investigations.
Here, we report a draft genome sequence of the strain Coralloluteibacterium stylophorae LMG 29479T, acquired from the Belgian Coordinated Collections of Microorganisms. The genus ...Coralloluteibacterium currently includes only one species with a validly published name. These genome sequencing data are important for the phylogeny of the Lysobacteraceae family.
In this report, we present a draft genome sequence of Bacillus amyloliquefaciens strain B-1895. Comparison with the genome of a reference strain demonstrated similar overall organization, as well as ...differences involving large gene clusters.
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