Identification of Brucella RS15060 As a Novel Type IV Secretion System Effector Associated with Bacterial Virulence

Overview

Journal Vet Res

Publisher Biomed Central

Specialty Veterinary Medicine

Date 2024 Dec 19

PMID 39696601

Authors

Yi Yin

Mingxing Tian

Guangdong Zhang

Hai Hu

Chan Ding

Shengqing Yu

Affiliations

Soon will be listed here.

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.

References

Marchesini M, Herrmann C, Salcedo S, Gorvel J, Comerci D . In search of Brucella abortus type IV secretion substrates: screening and identification of four proteins translocated into host cells through VirB system. Cell Microbiol. 2011; 13(8):1261-74. PMC: 3139020. DOI: 10.1111/j.1462-5822.2011.01618.x. View

Baertling F, Sanchez-Caballero L, van den Brand M, Fung C, Chan S, Wong V . NDUFA9 point mutations cause a variable mitochondrial complex I assembly defect. Clin Genet. 2017; 93(1):111-118. DOI: 10.1111/cge.13089. View

Ke Y, Wang Y, Li W, Chen Z . Type IV secretion system of Brucella spp. and its effectors. Front Cell Infect Microbiol. 2015; 5:72. PMC: 4602199. DOI: 10.3389/fcimb.2015.00072. View

van den Bosch B, Gerards M, Sluiter W, Stegmann A, Jongen E, Hellebrekers D . Defective NDUFA9 as a novel cause of neonatally fatal complex I disease. J Med Genet. 2011; 49(1):10-5. DOI: 10.1136/jmedgenet-2011-100466. View

He Y, Reichow S, Ramamoorthy S, Ding X, Lathigra R, Craig J . Brucella melitensis triggers time-dependent modulation of apoptosis and down-regulation of mitochondrion-associated gene expression in mouse macrophages. Infect Immun. 2006; 74(9):5035-46. PMC: 1594834. DOI: 10.1128/IAI.01998-05. View

Xiong X, Li B, Zhou Z, Gu G, Li M, Liu J . The VirB System Plays a Crucial Role in Intracellular Infection. Int J Mol Sci. 2021; 22(24). PMC: 8707931. DOI: 10.3390/ijms222413637. View

Cheng Z, Li Z, Yin Y, Lian Z, Abdelgawad H, Hu H . Characteristics of Brucella abortus vaccine strain A19 reveals its potential mechanism of attenuated virulence. Vet Microbiol. 2021; 254:109007. DOI: 10.1016/j.vetmic.2021.109007. View

de Barsy M, Jamet A, Filopon D, Nicolas C, Laloux G, Rual J . Identification of a Brucella spp. secreted effector specifically interacting with human small GTPase Rab2. Cell Microbiol. 2011; 13(7):1044-58. DOI: 10.1111/j.1462-5822.2011.01601.x. View

Islam R, Brown S, Taheri A, Dumenyo C . The Gene Encoding NAD-Dependent Epimerase/Dehydratase, , Affects Cell Surface Properties, Virulence, and Extracellular Enzyme Production in the Soft Rot Phytopathogen, . Microorganisms. 2019; 7(6). PMC: 6616942. DOI: 10.3390/microorganisms7060172. View

10.

Moreno E, Cloeckaert A, Moriyon I . Brucella evolution and taxonomy. Vet Microbiol. 2002; 90(1-4):209-27. DOI: 10.1016/s0378-1135(02)00210-9. View

11.

Gimenez A, Del Giudice M, Lopez P, Guaimas F, Samano-Sanchez H, Gibson T . NpeA is a secreted Type IV effector containing an N-WASP-binding short linear motif that promotes niche formation. mBio. 2024; 15(7):e0072624. PMC: 11253601. DOI: 10.1128/mbio.00726-24. View

12.

Ma Z, Li R, Hu R, Deng X, Xu Y, Zheng W . BspJ Is a Nucleomodulin That Inhibits Macrophage Apoptosis and Promotes Intracellular Survival of . Front Microbiol. 2020; 11:599205. PMC: 7688787. DOI: 10.3389/fmicb.2020.599205. View

13.

Atluri V, Xavier M, de Jong M, den Hartigh A, Tsolis R . Interactions of the human pathogenic Brucella species with their hosts. Annu Rev Microbiol. 2011; 65:523-41. DOI: 10.1146/annurev-micro-090110-102905. View

14.

Luizet J, Raymond J, Lacerda T, Barbieux E, Kambarev S, Bonici M . The effector BspL targets the ER-associated degradation (ERAD) pathway and delays bacterial egress from infected cells. Proc Natl Acad Sci U S A. 2021; 118(32). PMC: 8364137. DOI: 10.1073/pnas.2105324118. View

15.

Whatmore A . Current understanding of the genetic diversity of Brucella, an expanding genus of zoonotic pathogens. Infect Genet Evol. 2009; 9(6):1168-84. DOI: 10.1016/j.meegid.2009.07.001. View

16.

Llosa M, Roy C, Dehio C . Bacterial type IV secretion systems in human disease. Mol Microbiol. 2009; 73(2):141-51. PMC: 2784931. DOI: 10.1111/j.1365-2958.2009.06751.x. View

17.

Loeffen J, Triepels R, van den Heuvel L, Schuelke M, Buskens C, Smeets R . cDNA of eight nuclear encoded subunits of NADH:ubiquinone oxidoreductase: human complex I cDNA characterization completed. Biochem Biophys Res Commun. 1999; 253(2):415-22. DOI: 10.1006/bbrc.1998.9786. View

18.

Cascales E, Christie P . The versatile bacterial type IV secretion systems. Nat Rev Microbiol. 2004; 1(2):137-49. PMC: 3873781. DOI: 10.1038/nrmicro753. View

19.

Boschiroli M, Ouahrani-Bettache S, Foulongne V, Michaux-Charachon S, Bourg G, Allardet-Servent A . The Brucella suis virB operon is induced intracellularly in macrophages. Proc Natl Acad Sci U S A. 2002; 99(3):1544-9. PMC: 122227. DOI: 10.1073/pnas.032514299. View

20.

Louche A, Blanco A, Lacerda T, Cancade-Veyre L, Lionnet C, Berge C . Brucella effectors NyxA and NyxB target SENP3 to modulate the subcellular localisation of nucleolar proteins. Nat Commun. 2023; 14(1):102. PMC: 9823007. DOI: 10.1038/s41467-022-35763-8. View