Premium
The Lon‐2 protease of Borrelia burgdorferi is critical for infection in the mammalian host
Author(s) -
Mason Charlotte,
Thompson Christina,
Ouyang Zhiming
Publication year - 2020
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/mmi.14460
Subject(s) - borrelia burgdorferi , rpos , biology , mutant , infectivity , microbiology and biotechnology , spirochaetaceae , wild type , mutation , phenotype , protease , genetics , gene , gene expression , enzyme , antibody , biochemistry , virus , promoter
Abstract Borrelia burgdorferi encodes a functional homolog of canonical Lon protease termed Lon‐2. To date, the contribution of Lon‐2 to B. burgdorferi fitness and infection remains unexplored. Herein, we showed that expression of lon‐2 was highly induced during animal infection, suggesting that Lon‐2 is important for B. burgdorferi infection. We further generated a lon‐2 deletion mutant. Compared with that of wild‐type (WT) strain, the infectivity of the mutant was severely attenuated in a murine infection model. Although no growth defect was observed for the mutant in normal BSK‐II medium, resistance of the lon‐2 mutant to osmotic stress was markedly reduced. In addition, when exposed to tert ‐Butyl hydroperoxide, survival of the lon‐2 mutant was impaired. In addition, we found that the protein levels of RpoS and RpoS‐dependent OspC were decreased in the mutant. All these phenotypes were restored to WT or near‐WT levels when lon‐2 mutation was complemented in cis . Taken together, these results demonstrate that Lon‐2 is critical for B. burgdorferi to establish infection and to cope with environmental stresses. This study provides a foundation for further uncovering the direct link between the dual roles of Lon‐2 in protein quality control and bacterial pathogenesis.