Identification of Brucella RS15060 as a novel type IV secretion system effector associated with bacterial virulence
Year: 2024
Type: article
Abstract: Brucella is an intracellular parasitic pathogen that causes the worldwide zoonotic disease brucellosis. The type IV secretion system (T4SS) is utilized to secrete various effectors to help Brucella form Brucella-containing vacuoles within the cell and accomplish intracellular trafficking and replication. Brucella has fewer recognized effector proteins than other intracellular parasites in the Proteobacteria, indicating that Brucella may contain a large number of unidentified effector proteins. In this study, the optimal conditions for inducing protein secretion from Brucella were screened, and the secreted proteins of 2308 and the T4SS-deficient mutant SV123 under optimal conditions were collected for comparative proteomics analysis. By label-free quantitative proteomics, we identified 15 differential proteins. Through the β-lactamase TEM1 assay and indirect immunofluorescence assay, we identified RS15060 and RS10635 as novel T4SS effectors. Furthermore, by constructing mutation strains and performing cell/mouse infection experiments, we found that deletion of the rs15060 gene reduced the capacity of Brucella to replicate in cells and cause chronic infection in mice. In conclusion, a novel Brucella T4SS effector protein, RS15060, was identified to be associated with virulence in this study, and the discovery of effector proteins is conducive to a more comprehensive elucidation of T4SS function as well as to uncovering the cryptic strategies of Brucella survival in cells.
Source: Veterinary Research
Language: English
Subfield: Small Animals
Field: Veterinary
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,290
Award: G615616696
OpenAlex ID: W4405510523