Open AccessThe Relapsing Fever Spirochete Borrelia hermsii Contains Multiple, Antigen-Encoding Circular Plasmids That Are Homologous to the cp32 Plasmids of Lyme Disease Spirochetes
Author(s) -
Brian Stevenson,
Stephen F. Porcella,
Katrina L. Oie,
Cecily A. Fitzpatrick,
Sandra J. Raffel,
Lori Lubke,
Merry E. Schrumpf,
Tom G. Schwan
Publication year - 2000
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.68.7.3900-3908.2000
Subject(s) - biology , borrelia burgdorferi , plasmid , relapsing fever , spirochaetaceae , virology , borrelia , microbiology and biotechnology , lyme disease , gene , genetics , antibody
Borrelia hermsii , an agent of tick-borne relapsing fever, was found to contain multiple circular plasmids approximately 30 kb in size. Sequencing of a DNA library constructed from circular plasmid fragments enabled assembly of a composite DNA sequence that is homologous to the cp32 plasmid family of the Lyme disease spirochete,B. burgdorferi . Analysis of another relapsing fever bacterium,B. parkeri , indicated that it contains linear homologs of theB. hermsii andB. burgdorferi cp32 plasmids. TheB. hermsii cp32 plasmids encode homologs of theB. burgdorferi Mlp and Bdr antigenic proteins and BlyA/BlyB putative hemolysins, but homologs ofB. burgdorferi erp genes were absent. Immunoblot analyses demonstrated that relapsing fever patients produced antibodies to Mlp proteins, indicating that those proteins are synthesized by the spirochetes during human infection. Conservation of cp32-encoded genes in differentBorrelia species suggests that their protein products serve functions essential to both relapsing fever and Lyme disease spirochetes. Relapsing fever borreliae replicate to high levels in the blood of infected animals, permitting direct detection and possible functional studies of Mlp, Bdr, BlyA/BlyB, and other cp32-encoded proteins in vivo.