BosR (BB0647) governs virulence expression in Borrelia burgdorferi.
Summary Borrelia burgdorferi (Bb), the Lyme disease spirochaete, encodes a potential ferric uptake regulator (Fur) homologue, BosR (BB0647). Thus far, a role for BosR in Bb metabolism, gene regulation or pathogenesis has not been determined, largely due to the heretofore inability to inactivate bosR in low-passage, infectious Bb isolates. Herein, we report the generation of the first bosR-deficient mutant in a virulent strain of Bb. Whereas the bosR mutant persisted normally in ticks, the mutant was unable to infect mice, indicating that BosR is essential for Bb infection of a mammalian host. Moreover, transcriptional profiling of the bosR mutant showed that a number of genes were either positively or negatively influenced by BosR deficiency, suggesting that BosR may function both as a global repressor and activator in Bb. Strikingly, our study showed that BosR controls the expression of two major virulence-associated Bb lipoproteins, OspC and DbpA, likely via an influence on the alternative sigma factor, RpoS. This study thus not only has elucidated another key virulence gene of Bb, but also provides new insights into a previously unknown layer of gene regulation governing RpoS in Bb.
Ouyang
Zhiming
Z
Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
Kumar
Manish
M
Kariu
Toru
T
Haq
Shayma
S
Goldberg
Martin
M
Pal
Utpal
U
Norgard
Michael V
MV
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology*; D025065:Borrelia burgdorferi / Q000235:genetics / Q000472:pathogenicity*; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D055786:Gene Knockout Techniques; D006801:Humans; D008193:Lyme Disease / Q000382:microbiology*; D051379:Mice; D013987:Ticks / Q000382:microbiology; D014774:Virulence; D037521:Virulence Factors / Q000096:biosynthesis* / Q000235:genetics
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D037521:Virulence Factors