The objectives of this project are to (1) use recombinant DNA techniques to express specific antigens of Borrelia burgdorferi to improve the serodiagnosis of Lyme disease, (2) characterize at the molecular level, isolates of the Lyme disease spirochete from a wide range of biological and geographical sources, and (3) identify molecular determinants of the spirochete that are important for infectivity in mammalian and tick hosts. As part of our continued interest in the 39 kilodalton (P39) protein of B. burgdorferi as a diagnostic antigen, analyses were completed with other species of bacteria. Five serovars of Leptospira interrogans, L. biflexa, Leptonema illini, and Rickettsia rickettsii were examined and found not to contain this antigen. The specificity of this antigen and its reactivity with human Lyme disease sera should exclude the possibility of false-positive serum samples from patients having had either leptospirosis or Rocky Mountain spotted fever, as well as tick-borne relapsing fever and syphilis, as we discussed in previous reports. We have examined 31 isolates of B. burgdorferi from pools of Ixodes pacificus ticks collected from numerous regions spanning most of the state of California where this tick is found. All isolates were identified as B. burgdorferi by their reactivities with monoclonal antibodies to outer surface proteins A and B, flagellin, and the 39 kDa (P39) protein. By polymerase chain reaction (PCR) assays, all of the isolates reacted as North American-type B. burgdorferi. Plasmid profiles were quite diverse and only lo of 27 isolates examined contained the small 8 kilobase supercoiled plasmid we described previously. One isolate was made from ticks collected at Wawona Campground in Yosemite National Park, documenting the occurrence of the Lyme spirochete in an area of extreme human recreational use. We have also developed a rapid technique to identify small supercoiled plasmids by photonicking the supercoiled molecules with UV light and ethidium bromide in agarose gels. This allows us to then identify newly-formed open circular molecules that migrate slower than supercoiled molecules in the gel.
Oguge, N O; Durden, L A; Keirans, J E et al. (2009) Ectoparasites (sucking lice, fleas and ticks) of small mammals in southeastern Kenya. Med Vet Entomol 23:387-92 |
Lopez, Job E; Schrumpf, Merry E; Raffel, Sandra J et al. (2008) Relapsing fever spirochetes retain infectivity after prolonged in vitro cultivation. Vector Borne Zoonotic Dis 8:813-20 |
Gill, James S; Ullmann, Amy J; Loftis, Amanda D et al. (2008) Novel relapsing fever spirochete in bat tick. Emerg Infect Dis 14:522-3 |
Mans, Ben J; Andersen, John F; Schwan, Tom G et al. (2008) Characterization of anti-hemostatic factors in the argasid, Argas monolakensis: implications for the evolution of blood-feeding in the soft tick family. Insect Biochem Mol Biol 38:22-41 |
Battisti, James M; Raffel, Sandra J; Schwan, Tom G (2008) A system for site-specific genetic manipulation of the relapsing fever spirochete Borrelia hermsii. Methods Mol Biol 431:69-84 |
Dworkin, Mark S; Schwan, Tom G; Anderson Jr, Donald E et al. (2008) Tick-borne relapsing fever. Infect Dis Clin North Am 22:449-68, viii |
Mans, Ben J; Andersen, John F; Francischetti, Ivo M B et al. (2008) Comparative sialomics between hard and soft ticks: implications for the evolution of blood-feeding behavior. Insect Biochem Mol Biol 38:42-58 |
Whitney, Marlyn S; Schwan, Tom G; Sultemeier, Katherine B et al. (2007) Spirochetemia caused by Borrelia turicatae infection in 3 dogs in Texas. Vet Clin Pathol 36:212-6 |
Pettersson, Jonas; Schrumpf, Merry E; Raffel, Sandra J et al. (2007) Purine salvage pathways among Borrelia species. Infect Immun 75:3877-84 |
Schwan, Tom G; Raffel, Sandra J; Schrumpf, Merry E et al. (2007) Diversity and distribution of Borrelia hermsii. Emerg Infect Dis 13:436-42 |
Showing the most recent 10 out of 37 publications