Omp16, a conserved peptidoglycan-associated lipoprotein, is involved in Brucella virulence in vitro
- PDF / 1,480,636 Bytes
- 12 Pages / 612 x 792 pts (letter) Page_size
- 89 Downloads / 158 Views
eISSN 1976-3794 pISSN 1225-8873
Omp16, a conserved peptidoglycan-associated lipoprotein, is involved in Brucella virulence in vitro Feijie Zhi1†, Dong Zhou1,2†, Junmei Li1, Lulu Tian1, Guangdong Zhang1, Yaping Jin1,2*, and Aihua Wang1* 1
College of Veterinary Medicine, Northwest A&F University, Yangling, P. R. China 2 Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Yangling, P. R. China (Received Mar 17, 2020 / Revised Jun 2, 2020 / Accepted Jul 9, 2020)
Brucella, the bacterial agent of common zoonotic brucellosis, primarily infects specific animal species. The Brucella outer membrane proteins (Omps) are particularly attractive for developing vaccine and improving diagnostic tests and are associated with the virulence of smooth Brucella strains. Omp16 is a homologue to peptidoglycan-associated lipoproteins (Pals), and an omp16 mutant has not been generated in any Brucella strain until now. Very little is known about the functions and pathogenic mechanisms of Omp16 in Brucella. Here, we confirmed that Omp16 has a conserved Pal domain and is highly conserved in Brucella. We attempted to delete omp16 in Brucella suis vaccine strain 2 (B. suis S2) without success, which shows that Omp16 is vital for Brucella survival. We acquired a B. suis S2 Omp16 mutant via conditional complementation. Omp16 deficiency impaired Brucella outer membrane integrity and activity in vitro. Moreover, inactivation of Omp16 decreased bacterial intracellular survival in macrophage RAW 264.7 cells. B. suis S2 and its derivatives induced marked expression of IL-1β, IL-6, and TNF-α mRNA in Raw 264.7 cells. Whereas inactivation of Omp16 in Brucella enhanced IL-1β and IL-6 expression in Raw 264.7 cells. Altogether, these findings show that the Brucella Omp16 mutant was obtained via conditional complementation and confirmed that Omp16 can maintain outer membrane integrity and be involved in bacterial virulence in Brucella in vitro and in vivo. These results will be important in uncovering the pathogenic mechanisms of Brucella. Keywords: B. suis S2, Omp16, conditional expression, tetracycline, attenuation
† These authors contributed equally to this work. *For correspondence. (Y. Jin) E-mail: [email protected] / (A. Wang) E-mail: [email protected] Copyright G2020, The Microbiological Society of Korea
Introduction Brucellosis, one of the most common zoonotic infectious diseases, is caused by Brucella spp., which tend to infect specific animal species and humans (von Bargen et al., 2012; de Figueiredo et al., 2015). The characteristics of brucellosis are infertility and reproductive losses with predilection in animals (Olsen and Palmer, 2014). Recurrent fever and debilitating musculoskeletal, cardiac and neurological complications are the main clinical symptoms of chronic brucellosis in humans (Celli, 2015). Economic losses, human morbidity, and poverty have become increasingly serious worldwide with the continuous spread of brucellosis. More than half a million new cases are reported worldwide an
Data Loading...
