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DNA was extracted from pools of Amblyomma americanum ticks collected from vegetation at two sites in Fort Leonard Wood, Missouri and tested for the presence of Borrelia spp. Two new methods were developed to detect Borrelia lonestari DNA by targeting the glycerophosphodiester phosphodiesterase (glpQ) gene. The first method detected B. lonestari DNA using a SYBR green I melting curve analysis of the PCR product obtained with glpQ gene primers. The second method, a glpQ TaqMan assay, detected and confirmed the presence of B. lonestari glpQ-specific sequences. Twenty-two of 95 tick pools collected at site A148 contained B. lonestari DNA. None of 19 pools from site A241 contained B. lonestari DNA. No B. burgdorferi sensu lato DNA was detected using a SYBR green I melting curve analysis of the PCR product obtained with outer surface protein A (ospA) primers. The overall B. lonestari infection prevalence (with 95% confidence interval) at site A148 was estimated using two algorithms: minimum infection rate 4.14% (2.45, 5.84) and maximum likelihood with correction 4.82% (3.11, 7.16). The merits of each are discussed. Sequencing of the entire B. lonestari glpQ and partial 16S rRNA genes revealed two genetic variants circulating in this population of A. americanum from Missouri.

We have generated a panel of IgG monoclonal antibodies (MAbs) directed against Borrelia burgdorferi strain B31 antigens, using a method whereby mice were primed with organisms naturally inoculated by Ixodes scapularis nymphal ticks. Western blot analysis showed that these MAbs recognized several B. burgdorferi B31 antigens, including the complement inhibitor factor H-binding proteins ErpA/I/N and ErpC. Two other MAbs were specific for the RevA protein, and have enabled characterization of that previously unknown protein. The data presented here suggest that the production of MAbs from animals infected by tick-bite is a potentially useful tool for the identification of novel proteins synthesized by B. burgdorferi during mammalian infection.

A simple and efficient mutagenesis procedure is described which uses both the 3′→5′ exonuclease and 5′→3′ polymerase activities of T4 DNA polymerase. Different types of mutation—deletion, insertion, and substitution—can be introduced into the DNA in a single reaction. The technique uses recombinant M13 single-stranded DNA and two complementary DNA oligonucleotides to target and control the extent of deletions catalyzed by T4 DNA polymerase. The second oligonucleotide not only directs ligation, but also serves as a template for insertion or substitution of nucleotides by T4 polymerase. Mutant phages in a genetically pure form can be obtained at high efficiency, allowing their characterization directly by nucleotide sequencing without prior enrichment, plaque purification, and screening. We tested the versatility of this method by manipulating five regions of cDNA encoding the structural proteins of eastern equine encephalitis virus.