Identification of a wza-like gene involved in capsule biosynthesis, pathogenicity and biofilm formation in Riemerella anatipestifer. (June 2017)

• Record Type: Journal Article
• Authors: Yi, Haibo; Yuan, Biao; Liu, Jibin; Zhu, Dekang; Wu, Ying; Wang, Mingshu; Jia, Renyong; Sun, Kunfeng; Yang, Qiao; Chen, Shun; Liu, Mafeng; Chen, Xiaoyue; Cheng, Anchun
• Is Part Of: Microbial pathogenesis. Volume 107(2017)
• Page Start: 442
• Page End: 450
• Publication Date: 2017-06
• Subjects: Riemerella anatipestifer -- wza -- Capsule -- Virulence -- Biofilm formation; RA Riemerella anatipestifer -- CPS capsular polysaccharides -- PBS phosphate-buffered saline -- TSA tryptic soya agar -- TSB tryptic soy broth -- PCR polymerase chain reaction -- ORF open reading frame -- NCBI national center of biotechnology information -- BLAST basic local alignment search tool -- CDD conserved domain database -- LD50 median lethal dose -- NDS normal duck serum -- HDS heat-inactivated duck serum -- CFU colony forming units -- Spec spectinomycin -- Cm chloramphenicol -- Cfx cefoxitin; Pathogenic microorganisms -- Periodicals; Pathology, Molecular -- Periodicals; Communicable Diseases -- microbiology -- Periodicals; Communicable Diseases -- parasitology -- Periodicals; Micro-organismes pathogènes -- Périodiques; Pathologie moléculaire -- Périodiques; Electronic journals; 616.9041
• DOI: 10.1016/j.micpath.2017.04.023
• Languages: English
• ISSNs: 0882-4010

Abstract

Abstract: Duck infectious serositis is the most serious bacterial disease of ducks. It is caused by Riemerella anatipestifer (RA) infection. The capsule plays an important role in virulence of many pathogenic bacteria. In addition, the capsule has some key biological features. However, few studies have explored the characteristics of the RA capsule. In this study, we mainly constructed a capsular mutants of RA by inactivating the wza gene using homologous recombination. We found that the mutant was failed to produce a capsule layer. The mutant was less resistant to killing by the host complement or by desiccation and oxidative stress. Furthermore, the mutant strain was more hydrophobic, more able to auto-aggregate and underwent increased biofilm formation. Moreover, the mutant was less virulent than the wild-type in vivo studies. In summary, we found that the RA capsule was involved in the desiccation and oxidative stress, surface hydrophobicity, complement-mediated killing, biofilm formation, and virulence. Highlights: Riemerella anatipestifer wza gene was responsible for the assembly of the CPS but not for that of the LPS-O-antigen. wza gene is a virulence gene. The product of wza is resistant to the serum killing. wza gene is involved in hydrophobic, auto-aggregation and biofilm formation. wza is also involved in other biological features of Riemerella anatipestifer .