%0 Journal Article %T DGGE Identification of Microorganisms Associated with Borrelia burgdorferi Sensu Lato- or Anaplasma phagocytophilum-Infected Ixodes ricinus Ticks from Northwest Norway %A Ann-Kristin Tveten %A Andreas Riborg %A Hanne Tjelle Vadseth %J International Journal of Microbiology %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/805456 %X Ticks acquire a wide range of microorganisms as a natural part of their lifecycle. Bacteria, viruses, and protozoa can be transmitted to ticks during feeding and free-living phases. DGGE profiling is a molecular method to describe the microbial population associated with ticks and demonstrate some of the complexity and variety of tick-borne microorganisms. The present study profiled a total of 120 I. ricinus ticks, which were divided into three equally sized groups. We found that B. burgdorferi s.l.-infected ticks presented a pattern consisting of bacterial Pseudomonas spp. (67.5%), Bacillus spp. (50%), and Sphingomonas spp. (77.5%), while A. phagocytophilum-infected ticks were associated with Pseudomonas spp. (82.5%) and Sphingomonas spp. (57.5%). All profiles had one or more Pseudomonas species present, and the intramitochondrial endosymbiont Candidatus Midichloria mitochondrii was present in more than 25% of the samples. Statistical analysis demonstrated that the microbial communities were not significantly different between the groups and that the groups could not be characterised by a specific microbial population. 1. Introduction Complex microbial communities are found in most natural ecosystems and are composed of a great variety of microorganisms [1]. Ticks have the potential to acquire microorganisms in all stages of their lifecycle, and they are associated with a large diversity of bacteria, viruses, and protozoa [2]. Some of these microorganisms are pathogens that are acquired while feeding on various hosts, while others are related to the environment where ticks reside during their free-living phases [2, 3]. Tick-borne zoonoses can cause severe and fatal infections in both humans and animals [4]. A number of tick-borne pathogens such as bacteria, viruses, and protozoa have been linked to diseases such as Lyme disease (LD), anaplasmosis (formerly ehrlichiosis), tularaemia, babesiosis, and tick-borne encephalitis virus (TBEV) [5]. Borrelia burgdorferi sensu lato comprises a group of Borrelia species that cause LD worldwide, and in particular, three Borrelia genospecies¡ªBorrelia burgdorferi sensu stricto, Borrelia afzelii, and Borrelia garinii¡ªare associated with human disease in Europe [6¨C8]. A fourth genospecies has been identified among Norwegian ticks: Borrelia valaisiana [9]. The prevalence of Lyme disease along the Norwegian coastline varies from approximately 25% in southern Norway to a prevalence of 14¨C18% in northwest Norway [9¨C11]. Anaplasma phagocytophilum causes a tick-borne rickettsial infection known as anaplasmosis [12, 13]. %U http://www.hindawi.com/journals/ijmicro/2013/805456/