An RND-Type Efflux System in Borrelia burgdorferi Is Involved in Virulence and Resistance to Antimicrobial Compounds
(A) Schematic representation of besC, becA and besB genes in the Borrelia burgdorferi B31 chromosome, insertion of the aadA gene cassette by homologous recombination and complementation plasmid. Arrows indicate the relative positions of the oligonucleotides used. The diagram is not drawn to scale. (B) PCR analysis of the wild-type strain, the resulting besC mutant and the complemented strain using primer pairs specific either only for the besC and aadA genes; or one primer specific for besA and the other for aadA gene. The PCR was also used to confirm the presence of the shuttle vector in the complemented strain using one primer specific for besC and another specific for the shuttle vector. (C) Immunoblotting using antiserum raised against BesA, BesB and BesC to determine the presence or absence of these proteins in wild-type, besC mutant and the complemented strain.