Browsing by Subject "tick"
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Item All About Lyme Disease(2009-09-16) MacAfee, LaurenLyme disease and tick bites are very common in Minnesota. This patient brochure discusses common features of Lyme disease, including diagnosis, treatment, and prevention.Item Experimental data associated with the study "The Ixodes scapularis symbiont Rickettsia buchneri inhibits growth of pathogenic Rickettsiaceae in tick cells: implications for vector competence"(2021-11-10) Cull, Benjamin; Burkhardt, Nicole Y; Wang, XinRu; Thorpe, Cody J; Oliver, Jonathan D; Kurtti, Timothy J; Munderloh, Ulrike G; cull0122@umn.edu; Cull, Benjamin; Munderloh/Kurtti tick lab, Department of EntomologyThese experimental data are made available as part of the study "The Ixodes scapularis symbiont Rickettsia buchneri inhibits growth of pathogenic Rickettsiaceae in tick cells: implications for vector competence" published in Frontiers in Veterinary Science. Abstract: The blacklegged tick Ixodes scapularis is a vector of pathogens of medical and veterinary importance in North America. Unlike other important human-biting Ixodes species however, this tick does not transmit pathogenic Rickettsia species, instead hosting a rickettsial endosymbiont, Rickettsia buchneri. A gene cluster encoding aminoglycoside antibiotic biosynthesis machinery has been identified in R. buchneri, which is not present in other rickettsiae, and therefore antibiotic production might represent a mechanism by which the endosymbiont is able to exclude pathogenic Rickettsia species from I. scapularis. This study identifies a second antibiotic cluster in R. buchneri with genes similar to polyketide/non-ribosomal peptide synthesis genes. Using cell culture experiments we provide evidence that infection of tick cells with R. buchneri, even at low rates, significantly reduces the ability of the pathogens Anaplasma phagocytophilum and R. parkeri to infect and replicate in cells, whereas the presence of low-pathogenic R. amblyommatis or the endosymbiotic R. peacockii in cells only partially reduced infection by R. parkeri. This research suggests a potential role of the endosymbiont in preventing other rickettsiae from colonizing I. scapularis and/or being transmitted transovarially. Whilst a link between the observed inhibition and antibiotic production is yet to be confirmed, this work contributes further to our understanding of rickettsial competition and how endosymbionts might alter vector competence by preventing colonization of the tick by pathogens.Item Lyme Disease Prevention(2008-09-02) Bantle, AnnePatients in Minnesota are often bitten by ticks, and may be worried about their risk of Lyme disease. This brochure provides information on how to avoid tick bites, how to recognize Lyme disease, and when antibiotics are needed.Item Molecular analysis of the transfer (tra) genes of Rickettsia bellii RML 369-C and their function in bacterial conjugation(2016-02) Heu, ChanRickettsia bellii is an obligate intracellular bacterium. Among the Rickettsiales, R. bellii is unusual because it encodes a complete set of transfer (tra) genes and pili-like structures associated with bacterial conjugation. To investigate the relationship of the tra genes with bacterial conjugation, I first characterized the tra genes into multiple operons and predicted the cellular localization of each of the Tra proteins using predicted transmembrane-spanning domains and signal peptides in the context of current knowledge of the bacterial conjugation system used by E. coli. I also characterized the transcriptional dynamics of R. bellii tra genes in comparison to stably transcribed genes to understand when the tra genes are actively transcribed during the rickettsial life cycle. I determined that the best reference genes, out of 10 tested, were methionyl tRNA ligase (metG) or a combination of metG and ribonucleoside diphosphate reductase 2 subunit beta (nrdF), using statistical algorithms from two different programs: Normfinder and BestKeeper. The transcription of tra genes was positively correlated with one another and up-regulated from 12 to 72 hours post inoculation (HPI) when compared to RBE_0422 (an inactivated transposase-derivative found within the tra cluster) suggesting that bacterial conjugation may occur at later exponential growth or early stationary growth. Furthermore, a complementation assay was designed using traDF of R. bellii to rescue a traD mutant E. coli in transferring DNA. However, TraDF expression was not detected in two different E. coli expression strains. The data suggest that future experiments to express rickettsial Tra proteins in E. coli should be undertaken to exploit the R. bellii bacterial conjugation system and connect the rickettsial Tra proteins into functional genetic transfer systems.