Search results for "sequence"
showing 10 items of 4987 documents
Phylogeographical diversity of Anaplasma phagocytophilum in the Asian part of Russia based on multilocus sequence typing and analysis of the ankA gene
2019
Anaplasma phagocytophilum is a tick-transmitted bacterium that replicates in neutrophil granulocytes and elicits febrile disease in humans and animals; it is widely distributed in the Americas, Europe, Africa, and Asia. A. phagocytophilum is commonly regarded as a single species, but several genetic variants with distinct host distribution and geographical origin have been described. In a previous study, we used multilocus sequence typing (MLST) to characterize 25 A. phagocytophilum strains from Ixodes spp. ticks collected in the Asian part of Russia. The obtained concatenated sequences formed two separate clades reflecting their Asiatic origin and/or the vector species. As one of the clade…
Host and environmental factors affecting the intestinal microbiota in chickens
2018
The initial development of intestinal microbiota in poultry plays an important role in production performance, overall health and resistance against microbial infections. Multiplexed sequencing of 16S ribosomal RNA gene amplicons is often used in studies, such as feed intervention or antimicrobial drug trials, to determine corresponding effects on the composition of intestinal microbiota. However, considerable variation of intestinal microbiota composition has been observed both within and across studies. Such variation may in part be attributed to technical factors, such as sampling procedures, sample storage, DNA extraction, the choice of PCR primers and corresponding region to be sequenc…
High-throughput sequencing (HTS) for the analysis of viral populations
2020
The development of High-Throughput Sequencing (HTS) technologies is having a major impact on the genomic analysis of viral populations. Current HTS platforms can capture nucleic acid variation across millions of genes for both selected amplicons and full viral genomes. HTS has already facilitated the discovery of new viruses, hinted new taxonomic classifications and provided a deeper and broader understanding of their diversity, population and genetic structure. Hence, HTS has already replaced standard Sanger sequencing in basic and applied research fields, but the next step is its implementation as a routine technology for the analysis of viruses in clinical settings. The most likely appli…
First phenotypic and genotypic description of Fasciola hepatica infecting highland cattle in the state of Mexico, Mexico
2018
Abstract Fascioliasis is a plantborne and zoonotic parasitic disease caused by fasciolid liver flukes. Fasciola hepatica is the only fasciolid species described in the Americas. Human fascioliasis endemic areas are mainly located in high altitude areas of the Americas. Given the necessity to characterize F. hepatica populations involved, the phenotypic and genotypic features of fasciolid adults infecting cattle in the highland area of Toluca, State of Mexico, Mexico, were analyzed and compared to fasciolid materials from the Northern Bolivian Altiplano, representing the altiplanic transmission pattern in a hyperendemic scenario. A computer image analysis system (CIAS) was applied on the bas…
Prosthetic Valve Endocarditis with Bartonella washoensis in a Human European Patient and Its Detection in Red Squirrels ( Sciurus vulgaris )
2019
Members of the genus Bartonella are fastidious Gram-negative facultative intracellular bacteria that are typically transmitted by arthropod vectors. Several Bartonella spp. have been found to cause culture-negative endocarditis in humans. Here, we report the case of a 75-year old German woman with prosthetic valve endocarditis due to Bartonella washoensis. The infecting agent was characterized by sequencing of six housekeeping genes (16S rRNA, ftsZ, gltA, groEL, ribC, rpoB) applying a multilocus sequence typing (MLST) approach. The 5097 bp of the concatenated housekeeping gene sequence from the patient were 99.0% identical to a B. washoensis strain from a red squirrel (Sciurus vulgaris orie…
Draft genome sequence and biofilm production of a carbapenemase-producing Klebsiella pneumoniae (KpR405) sequence type 405 strain isolated in Italy
2021
Rapid identification and characterization of multidrug-resistant Klebsiella pneumoniae strains is essential to diagnose severe infections in patients. In clinical routine practice, K. pneumoniae is frequently identified and characterized for outbreak investigation. Pulsed-field gel electrophoresis or multilocus sequence typing could be used, but, unfortunately, these methods are time-consuming, laborious, expensive, and do not provide any information about the presence of resistance and virulence genes. In recent years, the decreasing cost of next-generation sequencing and its easy use have led to it being considered a useful method, not only for outbreak surveillance but also for rapid ide…
Molecular epidemiology and drug-resistance mechanisms in carbapenem-resistant Klebsiella pneumoniae isolated in patients from a tertiary hospital in …
2020
Abstract Objectives The aim of this study has been to characterize carbapenem-resistant Klebsiella pneumoniae isolates and to determine the resistance mechanisms involved, the clonal relationship between strains and clinical and demographical data of the infected patients. Methods Clinical and demographical data from patients were collected and statistically analysed. Antimicrobial susceptibility testing was performed and resistance genes were detected both phenotypically and genotypically. Conjugation assays were performed to show horizontal transferability of resistance genes. Clonal relationship was also studied. Next-generation sequencing (NGS) was performed to obtain information regard…
Development of a database for the rapid and accurate routine identification of Achromobacter species by matrix-assisted laser desorption/ionization-t…
2019
International audience; Objectives: Achromobacter spp. are emerging pathogens in respiratory samples from cystic fibrosis patients. The current reference methods (nrdA-sequencing or multilocus sequence typing) can identify 18 species which are often misidentified by conventional techniques as A. xylosoxidans. A few studies have suggested that matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) provides accurate identification of the genus but not of species. The aims of this study were (a) to generate a database for MALDI-TOF/MS Bruker including the 18 species, (b) to evaluate the suitability of the database for routine laboratory identification, and …
Characterization of the inner membrane protein BB0173 from Borrelia burgdorferi.
2017
Abstract Background The bacterial spirochete Borrelia burgdorferi is the causative agent of the most commonly reported arthropod-borne illness in the United States, Lyme disease. A family of proteins containing von Willebrand Factor A (VWFA) domains adjacent to a MoxR AAA+ ATPase have been found to be highly conserved in the genus Borrelia. Previously, a VWFA domain containing protein of B. burgdorferi, BB0172, was determined to be an outer membrane protein capable of binding integrin α3β1. In this study, the characterization of a new VWFA domain containing membrane protein, BB0173, is evaluated in order to define the location and topology of this multi-spanning membrane protein. In additio…
Plants assemble species specific bacterial communities from common core taxa in three arcto-alpine climate zones
2017
Evidence for the pivotal role of plant-associated bacteria to plant health and productivity has accumulated rapidly in the last years. However, key questions related to what drives plant bacteriomes remain unanswered, among which is the impact of climate zones on plant-associated microbiota. This is particularly true for wild plants in arcto-alpine biomes. Here, we hypothesized that the bacterial communities associated with pioneer plants in these regions have major roles in plant health support, and this is reflected in the formation of climate and host plant specific endophytic communities. We thus compared the bacteriomes associated with the native perennial plants Oxyria digyna and Saxi…