Publications by authors named "Thomas H A Haverkamp"

Background: Foodborne pathogens such as Campylobacter jejuni are responsible for a large proportion of the gastrointestinal infections worldwide associated with poultry meat. Campylobacter spp. can be found in the chicken fecal microbiome and can contaminate poultry meat during the slaughter process.

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Two isolates originating from two Norwegian dogs with acute hemorrhagic diarrhea were sequenced. Based on Illumina and Oxford Nanopore Technology sequencing, hybrid assemblies were generated, and one of the genomes was completed and closed. For both isolates, virulence genes and their genomic location have been identified.

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Introduction: Acute haemorrhagic diarrhoea syndrome (AHDS) in dogs is a condition of unknown aetiology. is suspected to play a role in the disease as it was commonly found in dogs suffering from AHDS during a Norwegian outbreak in 2019. The role of this bacterium as a constituent of the canine gut microbiota is unknown, hence this study set out to investigate its occurrence in healthy dogs using metagenomics.

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Previously, Klebsiella pneumoniae was found to occur more frequently in healthy turkey flocks than in healthy broiler flocks in Norway. This study aimed to investigate whether this higher occurrence could be attributed to a greater abundance of K. pneumoniae in turkey flocks.

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Eight Providencia alcalifaciens isolates from eight different dogs in Norway with acute hemorrhagic diarrhea were sequenced. Based on Illumina and Oxford Nanopore Technologies sequencing, all of the genomes were complete and closed after hybrid assembly.

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Phylogenomic analyses of bacteria from the phylum Thermotogota have shown extensive lateral gene transfer with distantly related organisms, particularly with Firmicutes. One likely mechanism of such DNA transfer is viruses. However, to date, only three temperate viruses have been characterized in this phylum, all infecting bacteria from the Marinitoga genus.

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Background: A severe form of acute hemorrhagic diarrhea syndrome (AHDS) occurred in dogs in the Oslo region of Norway during autumn 2019.

Objectives: To characterize the fecal microbiota of dogs with AHDS during the outbreak and compare it to that of healthy dogs from the same period and before the outbreak.

Animals: Dogs with AHDS (n = 50), dogs with nonhemorrhagic diarrhea (n = 3), and healthy dogs (n = 11) were sampled during the outbreak.

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In total, 12 quinolone-resistant (QREC) strains containing were submitted to long-read sequencing using a FLO-MIN106 flow cell on a MinION device. The long reads were assembled with short reads (Illumina) and analyzed using the MOB-suite pipeline. Six of these QREC genome sequences were closed after hybrid assembly.

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The relative importance of host-specific selection or environmental factors in determining the composition of the intestinal microbiome in wild vertebrates remains poorly understood. Here, we used metagenomic shotgun sequencing of individual specimens to compare the levels of intra- and interspecific variation of intestinal microbiome communities in two ecotypes (NEAC and NCC) of Atlantic cod () that have distinct behavior and habitats and three Gadidae species that occupy a range of ecological niches. Interestingly, we found significantly diverged microbiomes among the two Atlantic cod ecotypes.

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We announce five shotgun metagenomics data sets from two Norwegian premise plumbing systems. The samples were shotgun sequenced on two lanes of an Illumina HiSeq 3000 instrument (THRUplex chemistry, 151 bp, paired-end reads), providing an extensive resource for sequence analyses of tap water and biofilm microbial communities.

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Atlantic cod (Gadus morhua) is an ecologically important species with a wide-spread distribution in the North Atlantic Ocean, yet little is known about the diversity of its intestinal microbiome in its natural habitat. No geographical differentiation in this microbiome was observed based on 16S rRNA amplicon analyses, yet such finding may result from an inherent lack of power of this method to resolve fine-scaled biological complexity. Here, we use metagenomic shotgun sequencing to investigate the intestinal microbiome of 19 adult Atlantic cod individuals from two coastal populations in Norway-located 470 km apart.

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The genus Mesotoga, the only described mesophilic Thermotogae lineage, is common in mesothermic anaerobic hydrocarbon-rich environments. Besides mesophily, Mesotoga displays lineage-specific phenotypes, such as no or little H production and dependence on sulfur-compound reduction, which may influence its ecological role. We used comparative genomics of 18 Mesotoga strains (pairwise 16S rRNA identity >99%) and a transcriptome of M.

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Thermosipho species inhabit thermal environments such as marine hydrothermal vents, petroleum reservoirs, and terrestrial hot springs. A 16S rRNA phylogeny of available Thermosipho spp. sequences suggested habitat specialists adapted to living in hydrothermal vents only, and habitat generalists inhabiting oil reservoirs, hydrothermal vents, and hotsprings.

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Atlantic cod () provides an interesting species for the study of host-microbe interactions because it lacks the MHC II complex that is involved in the presentation of extracellular pathogens. Nonetheless, little is known about the diversity of its microbiome in natural populations. Here, we use high-throughput sequencing of the 16S rRNA V4 region, amplified with the primer design of the Earth Microbiome Project (EMP), to investigate the microbial composition in gut content and mucosa of 22 adult individuals from two coastal populations in Norway, located 470 km apart.

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Background: The expansion of offshore oil exploration increases the risk of marine species being exposed to oil pollution in currently pristine areas. The adverse effects of oil exposure through toxic properties of polycyclic aromatic hydrocarbons (PAHs) have been well studied in Atlantic cod (Gadus morhua). Nevertheless, the fate of conjugated metabolites in the intestinal tract and their effect on the diversity of intestinal microbial community in fish is less understood.

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Copper-silver ionization (CSI) is an in-house water disinfection method primarily installed to eradicate Legionella bacteria from drinking water distribution systems (DWDS). Its effect on the abundance of culturable Legionella and Legionella infections has been documented in several studies. However, the effect of CSI on other bacteria in DWDS is largely unknown.

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Background: Anthrax is a globally distributed disease affecting primarily herbivorous mammals. It is caused by the soil-dwelling and spore-forming bacterium Bacillus anthracis. The dormant B.

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The mosaic distribution of interbreeding taxa with contrasting ecology and morphology offers an opportunity to study microevolutionary dynamics during ecological divergence. We investigate here the evolutionary history of an alpine and a montane ecotype of Heliosperma pusillum (Caryophyllaceae) in the south-eastern Alps. From six pairs of geographically close populations of the two ecotypes (120 individuals) we obtained a high-coverage restriction site associated DNA sequencing (RADseq) dataset that was used for demographic inference to test the hypothesis of parallel evolution of the two ecotypes.

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Bacillus anthracis strains K1 and K2 were isolated from two plains zebra anthrax carcasses in Etosha National Park, Namibia. These are draft genomes obtained by Illumina MiSeq sequencing of isolates collected from culture of blood-soaked soil from each carcass.

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Oil reservoirs represent a nutrient-rich ecological niche of the deep biosphere. Although most oil reservoirs are occupied by microbial populations, when and how the microbes colonized these environments remains unanswered. To address this question, we compared 11 genomes of Thermotoga maritima-like hyperthermophilic bacteria from two environment types: subsurface oil reservoirs in the North Sea and Japan, and marine sites located in the Kuril Islands, Italy and the Azores.

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Background: Advances in sequencing efficiency have vastly increased the sizes of biological sequence databases, including many thousands of genome-sequenced species. The BLAST algorithm remains the main search engine for retrieving sequence information, and must consequently handle data on an unprecedented scale. This has been possible due to high-performance computers and parallel processing.

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Pockmarks are geological features that are found on the bottom of lakes and oceans all over the globe. Some are active, seeping oil or methane, while others are inactive. Active pockmarks are well studied since they harbor specialized microbial communities that proliferate on the seeping compounds.

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Background: The observation that specific members of the microbial intestinal community can be shared among vertebrate hosts has promoted the concept of a core microbiota whose composition is determined by host-specific selection. Most studies investigating this concept in individual hosts have focused on mammals, yet the diversity of fish lineages provides unique comparative opportunities from an evolutionary, immunological and environmental perspective. Here we describe microbial intestinal communities of eleven individual Atlantic cod (Gadus morhua) caught at a single location based on an extensively 454 sequenced 16S rRNA library of the V3 region.

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Background: Pockmarks (depressions in the seabed) have been discovered throughout the world's oceans and are often related to hydrocarbon seepage. Although high concentrations of pockmarks are present in the seabed overlaying the Troll oil and gas reservoir in the northern North Sea, geological surveys have not detected hydrocarbon seepage in this area at the present time. In this study we have used metagenomics to characterize the prokaryotic communities inhabiting the surface sediments in the Troll area in relation to geochemical parameters, particularly related to hydrocarbon presence.

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The incursion of High-Throughput Sequencing (HTS) in environmental microbiology brings unique opportunities and challenges. HTS now allows a high-resolution exploration of the vast taxonomic and metabolic diversity present in the microbial world, which can provide an exceptional insight on global ecosystem functioning, ecological processes and evolution. This exploration has also economic potential, as we will have access to the evolutionary innovation present in microbial metabolisms, which could be used for biotechnological development.

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