Lars Hestbjerg Hansen

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BACKGROUND Recent evidence suggests that there is a link between metabolic diseases and bacterial populations in the gut. The aim of this study was to assess the differences between the composition of the intestinal microbiota in humans with type 2 diabetes and non-diabetic persons as control. METHODS AND FINDINGS The study included 36 male adults with a(More)
Comparative whole-genome analyses have demonstrated that horizontal gene transfer (HGT) provides a significant contribution to prokaryotic genome innovation. The evolution of specific prokaryotes is therefore tightly linked to the environment in which they live and the communal pool of genes available within that environment. Here we use the term(More)
This review deals with the prospective, experimental documentation of horizontal gene transfer (HGT) and its role in real-time, local adaptation. We have focused on plasmids and their function as an accessory and/or adaptive gene pool. Studies of the extent of HGT in natural environments have identified certain hot spots, and many of these involve biofilms.(More)
The stability of mutualistic interactions is likely to be affected by the genetic diversity of symbionts that compete for the same functional niche. Fungus-growing (attine) ants have multiple complex symbioses and thus provide ample opportunities to address questions of symbiont specificity and diversity. Among the partners are Actinobacteria of the genus(More)
IncX plasmids are narrow host range plasmids of Enterobactericeae that have been isolated for over 50years. They are known to encode type IV fimbriae enabling their own conjugative transfer, and to provide accessory functions to their host bacteria such as resistance towards antimicrobial agents and biofilm formation. Previous plasmid-based replicon typing(More)
The presence and diversity of IncP-1 plasmids in the influent of a Danish wastewater treatment plant was studied by PCR amplification of the trfA gene in community DNA followed by sequencing. Three sets of PCR primers were designed to amplify a 281bp fragment of trfA from all currently sequenced IncP-1 plasmids. A neighbor-joining tree, based on a multiple(More)
The large conjugative multidrug resistance (MDR) plasmid pOLA52 was sequenced and annotated. The plasmid encodes two phenotypes normally associated with the chromosomes of opportunistic pathogens, namely MDR via a resistance-nodulation-division (RND)-type efflux-pump (oqxAB), and the formation of type 3 fimbriae (mrkABCDF). The plasmid was found to be(More)
OBJECTIVES A plasmid-encoded multidrug efflux pump, OqxAB, identified in Escherichia coli of porcine origin, was tested for substrate specificity against selected antibiotics, detergents and disinfectants. The ability of horizontal transfer to food-borne pathogens of the Enterobacteriaceae family was also investigated. METHODS The MICs of selected(More)
1. Disturbance is assumed to be a major driver of plant community composition, but whether similar processes operate on associated soil microbial communities is less known. Based on the assumed trade-off between disturbance tolerance and competiveness, we hypothesize that a severe disturbance applied within a semi-natural grassland would shift the(More)
Calcified dental plaque (dental calculus) preserves for millennia and entraps biomolecules from all domains of life and viruses. We report the first, to our knowledge, high-resolution taxonomic and protein functional characterization of the ancient oral microbiome and demonstrate that the oral cavity has long served as a reservoir for bacteria implicated in(More)