scholarly journals Phylogenetic analysis of Helicobacter pylori strains circulating in Yakutia by three housekeeping genes atpA, mutY, ppa

Author(s):  
Т.В. Борисова ◽  
Н.Н. Готовцев ◽  
Н.А. Барашков ◽  
М.В. Пак ◽  
М.П. Алексеева ◽  
...  

В работе представлен филогенетический анализ штаммов Helicobacter pylori, циркулирующих в Якутии, по данным трех генов домашнего хозяйства atpA, mutY, ppa. The work presents a phylogenetic analysis of Helicobacter pylori strains circulating in Yakutia, according to three housekeeping genes of the atpA, mutY, ppa.

2000 ◽  
Vol 44 (8) ◽  
pp. 2207-2210 ◽  
Author(s):  
Nadia Maggi Solcà ◽  
Marco Valerio Bernasconi ◽  
Jean-Claude Piffaretti

ABSTRACT The rdxA gene of 30 independently isolatedHelicobacter pylori strains was sequenced. A comparison of the rdxA sequences revealed a higher percentage of amino acid substitutions in the corresponding protein than in other housekeeping genes. Out of 122 point mutations, 41 were missense and 4 were nonsense. A resistant strain with a nucleotide insertion in therdxA sequence was also found. With the exception of the point mutations and the insertion generating a stop signal, no particular nucleotide mutation or amino acid substitution could be associated to metronidazole resistance. Moreover, phylogenetic analysis of the 30 nucleotide sequences did not demonstrate specific clusters associated with the resistance phenotype.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hongru Su ◽  
Eri Onoda ◽  
Hitoshi Tai ◽  
Hiromi Fujita ◽  
Shigetoshi Sakabe ◽  
...  

AbstractEhrlichia species are obligatory intracellular bacteria transmitted by arthropods, and some of these species cause febrile diseases in humans and livestock. Genome sequencing has only been performed with cultured Ehrlichia species, and the taxonomic status of such ehrlichiae has been estimated by core genome-based phylogenetic analysis. However, many uncultured ehrlichiae exist in nature throughout the world, including Japan. This study aimed to conduct a molecular-based taxonomic and ecological characterization of uncultured Ehrlichia species or genotypes from ticks in Japan. We first surveyed 616 Haemaphysalis ticks by p28-PCR screening and analyzed five additional housekeeping genes (16S rRNA, groEL, gltA, ftsZ, and rpoB) from 11 p28-PCR-positive ticks. Phylogenetic analyses of the respective genes showed similar trees but with some differences. Furthermore, we found that V1 in the V1–V9 regions of Ehrlichia 16S rRNA exhibited the greatest variability. From an ecological viewpoint, the amounts of ehrlichiae in a single tick were found to equal approx. 6.3E+3 to 2.0E+6. Subsequently, core-partial-RGGFR-based phylogenetic analysis based on the concatenated sequences of the five housekeeping loci revealed six Ehrlichia genotypes, which included potentially new Ehrlichia species. Thus, our approach contributes to the taxonomic profiling and ecological quantitative analysis of uncultured or unidentified Ehrlichia species or genotypes worldwide.


2006 ◽  
Vol 23 (8) ◽  
pp. 1493-1503 ◽  
Author(s):  
Morgan Kullberg ◽  
Maria A. Nilsson ◽  
Ulfur Arnason ◽  
Eric H. Harley ◽  
Axel Janke

1999 ◽  
Vol 67 (5) ◽  
pp. 2060-2070 ◽  
Author(s):  
Steffen Porwollik ◽  
Brian Noonan ◽  
Paul W. O’Toole

ABSTRACT Motility of Helicobacter species has been shown to be essential for successful colonization of the host. We have investigated the organization of a flagellar export locus in Helicobacter pylori. A 7-kb fragment of the H. pylori CCUG 17874 genome was cloned and sequenced, revealing an operon comprising an open reading frame of unknown function (ORF03), essential housekeeping genes (ileS and murB), flagellar export genes (fliI and fliQ), and a homolog to a gene implicated in virulence factor transport in other pathogens (virB11). A promoter for this operon, showing similarity to the Escherichia coli ς70 consensus, was identified by primer extension. Cotranscription of the genes in the operon was demonstrated by reverse transcription-PCR, and transcription of virB11, fliI, fliQ, andmurB was detected in human or mouse biopsies obtained from infected hosts. The genetic organization of this locus was conserved in a panel of H. pylori clinical isolates. EngineeredfliI and fliQ mutant strains were completely aflagellate and nonmotile, whereas a virB11 mutant still produced flagella. The fliI and fliQ mutant strains produced reduced levels of flagellin and the hook protein FlgE. Production of OMP4, a member of the outer membrane protein family identified in H. pylori 26695, was reduced in both thevirB11 mutant and the fliI mutant, suggesting related functions of the virulence factor export protein (VirB11) and the flagellar export component (FliI).


2007 ◽  
Vol 189 (6) ◽  
pp. 2339-2349 ◽  
Author(s):  
Michael Pflock ◽  
Melanie Bathon ◽  
Jennifer Schär ◽  
Stefanie Müller ◽  
Hans Mollenkopf ◽  
...  

ABSTRACT Helicobacter pylori is a gastric pathogen for which no nonhuman reservoir is known. In accordance with the tight adaptation to its unique habitat, the human stomach, H. pylori is endowed with a very restricted repertoire of regulatory proteins. Nevertheless, the three complete two-component systems of H. pylori were shown to be involved in the regulation of important virulence traits like motility and acid resistance and in the control of metal homeostasis. HP1021 is an orphan response regulator with an atypical receiver domain whose inactivation has a considerable impact on the growth of H. pylori. Here we report the identification of HP1021-regulated genes by whole-genome transcriptional profiling. We show that the transcription of the essential housekeeping genes nifS and nifU, which are required for the assembly of Fe-S clusters, is activated by HP1021. Furthermore, we demonstrate that the expression of a gene cluster comprising open reading frames hp0690 to hp0693 and hp0695 to hp0697 which is probably involved in acetone metabolism is strongly upregulated by HP1021. Evidence is provided for a direct regulation of the hp0695-to-hp0697 operon by the binding of HP1021 to its promoter region.


Gut Pathogens ◽  
2013 ◽  
Vol 5 (1) ◽  
pp. 33 ◽  
Author(s):  
Barik A Salih ◽  
Bora Bolek ◽  
Mehmet Yildiz ◽  
Soykan Arikan

2004 ◽  
Vol 54 (5) ◽  
pp. 1511-1519 ◽  
Author(s):  
L. Soler ◽  
M. A. Yáñez ◽  
M. R. Chacon ◽  
M. G. Aguilera-Arreola ◽  
V. Catalán ◽  
...  

The phylogenetic relationships of all known species of the genus Aeromonas, and especially Aeromonas bestiarum and Aeromonas salmonicida, were investigated on 70 strains using the rpoD sequence, which encodes the σ 70 factor. This analysis was complemented with the sequence of gyrB, which has already proven useful for determining the phylogenetic relationships in the genus. Nucleotide sequences of rpoD and gyrB showed that both genes had similar substitution rates (<2 %) and a similar number of variable positions (34 % for rpoD versus 32 % for gyrB). Strain groupings by analysis of rpoD, gyrB and a combination of both genes were consistent with the taxonomic organization of all Aeromonas species described to date. However, the simultaneous analysis of both clocks improved the reliability and the power to differentiate, in particular, closely related taxa. At the inter-species level, gyrB showed a better resolution for differentiating Aeromonas sp. HG11/Aeromonas encheleia and Aeromonas veronii/Aeromonas culicicola/Aeromonas allosaccharophila, while rpoD more clearly differentiated A. salmonicida from A. bestiarum. The analysis of rpoD provided initial evidence for clear phylogenetic divergence between the latter two species.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Abeer Babiker Idris ◽  
Hadeel Gassim Hassan ◽  
Maryam Atif Salaheldin Ali ◽  
Sulafa Mohamed Eltaher ◽  
Leena Babiker Idris ◽  
...  

Background. Helicobacter pylori (H. pylori) is ubiquitous among humans and one of the best-studied examples of an intimate association between bacteria and humans. Phylogeny and Phylogeography of H. pylori strains are known to mirror human migration patterns and reflect significant demographic events in human prehistory. In this study, we analyzed the molecular evolution of H. pylori strains detected from different tribes and regions of Sudan using 16S rRNA gene and the phylogenetic approach. Materials and methods. A total of 75 gastric biopsies were taken from patients who had been referred for endoscopy from different regions of Sudan. The DNA extraction was performed by using the guanidine chloride method. Two sets of primers (universal and specific for H. pylori) were used to amplify the 16S ribosomal gene. Sanger sequencing was applied, and the resulted sequences were matched with the sequences of the National Center for Biotechnology Information (NCBI) nucleotide database. The evolutionary aspects were analyzed using MEGA7 software. Results. Molecular detection of H. pylori has shown that 28 (37.33%) of the patients were positive for H. pylori and no significant differences were found in sociodemographic characteristics, endoscopy series, and H. pylori infection. Nucleotide variations were observed at five nucleotide positions (positions 219, 305, 578, 741, and 763–764), and one insertion mutation (750_InsC_751) was present in sixty-seven percent (7/12) of our strains. These six mutations were detected in regions of the 16S rRNA not closely associated with either tetracycline or tRNA binding sites; 66.67% of them were located in the central domain of 16S rRNA. The phylogenetic analysis of 16S rRNA sequences identified two lineages of H. pylori strains detected from different regions in Sudan. The presence of Sudanese H. pylori strains resembling Hungarian H. pylori strains could reflect the migration of Hungarian people to Sudan or vice versa. Conclusion. This finding emphasizes the significance of studying the phylogeny of H. pylori strains as a discriminatory tool to mirror human migration patterns. In addition, the 16S rRNA gene amplification method was found useful for bacterial identification and phylogeny.


2006 ◽  
Vol 74 (5) ◽  
pp. 3046-3051 ◽  
Author(s):  
Ewa E. Hennig ◽  
Johnna M. Allen ◽  
Timothy L. Cover

ABSTRACT Helicobacter pylori babA encodes an outer membrane protein that binds to fucosylated Lewis b blood group antigen. We analyzed a panel of 35 H. pylori strains and identified three possible chromosomal loci for babA. There was a significant association between the presence of babA and the presence of cagA (P = 0.0001). Phylogenetic analysis of babA alleles revealed two divergent families of signal sequences. Among 17 strains in which an intact in-frame babA allele was identified, 10 expressed a detectable BabA protein. Expression of a BabA protein and the Lewis b-binding phenotype were not dependent on the chromosomal locus of babA. These data indicate that there is marked heterogeneity among H. pylori strains in babA genetic content and BabA expression.


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