A second allele of eppA in Borrelia burgdorferi strain B31 is located on the previously undetected circular plasmid cp9-2.

@article{Miller2000ASA,
  title={A second allele of eppA in Borrelia burgdorferi strain B31 is located on the previously undetected circular plasmid cp9-2.},
  author={Jennifer C. Miller and James L Bono and Kelly Babb and Nazira El-Hage and Sherwood R. Casjens and Brian Stevenson},
  journal={Journal of bacteriology},
  year={2000},
  volume={182 21},
  pages={6254-8}
}
Although sequence analysis of Borrelia burgdorferi isolate B31 was recently declared "complete," we found that cultures of this strain can contain a novel 9-kb circular plasmid, cp9-2. The newly described plasmid contains both sequence similarities with and differences from the previously identified B31 plasmid cp9-1 (formerly cp9). cp9-1 and cp9-2 each encode a unique allele of EppA, a putative membrane protein synthesized by B. burgdorferi during mammalian infection.