Experimental assessment of the roles of linear plasmids lp25 and lp28-1 of Borrelia burgdorferi throughout the infectious cycle.
Borrelia burgdorferi, which causes Lyme disease in humans, has an unusual genome composed of a linear chromosome and up to 21 extrachromosomal elements. Experimental data suggest that two of these elements, linear plasmids lp25 and lp28-1, play essential roles for infectivity in mice. In this study, we prove the essential natures of these two plasmids by selectively displacing lp25 or lp28-1 in an infectious wild-type clone with incompatible shuttle vectors derived from the native plasmids, rendering the respective transformants noninfectious to mice. Conversely, restoration of plasmid lp25 or lp28-1 in noninfectious clones that naturally lack the corresponding plasmid reestablished infectivity in mice. This approach establishes the ability to manipulate the plasmid content of strains by eliminating or introducing entire plasmids in B. burgdorferi and will be valuable in assessing the roles of plasmids even in unsequenced B. burgdorferi strains.
Grimm
Dorothee
D
Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, USA.
Eggers
Christian H
CH
Caimano
Melissa J
MJ
Tilly
Kit
K
Stewart
Philip E
PE
Elias
Abdallah F
AF
Radolf
Justin D
JD
Rosa
Patricia A
PA
D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D015139:Blotting, Southern; D025065:Borrelia burgdorferi / Q000235:genetics* / Q000254:growth & development* / Q000276:immunology / Q000502:physiology; D004269:DNA, Bacterial / Q000235:genetics; D005819:Genetic Markers / Q000235:genetics; D007106:Immune Sera / Q000276:immunology; D008193:Lyme Disease / Q000382:microbiology; D051379:Mice; D010641:Phenotype; D010957:Plasmids / Q000235:genetics* / Q000502:physiology*; D013696:Temperature; D013987:Ticks / Q000382:microbiology
D000907:Antibodies, Bacterial; D004269:DNA, Bacterial; D005819:Genetic Markers; D007106:Immune Sera