Characterization and Evaluation of a Novel Conserved Membrane Antigen P35 of Mycoplasma synoviae.

Qianjin Sun,Wei Chen,Zhuanqiang Yan,Feng Chen,Qingfeng Zhou,Qian Zhong,Yongchang Cao,Xiaona Wei

doi:10.3389/fvets.2022.836110

Abstract

Mycoplasma synoviae (MS) is a major avian pathogen that causes respiratory damage, infectious synovitis, and arthritis in chickens and causes serious economic losses to the global poultry industry. Despite its significance, knowledge on pathogenicity and pathogenic mechanism of MS is lacking, especially regarding its antigens. Bioinformatic analysis showed that the known MS proteins are only the tip of the iceberg among many MS membrane proteins. In this study, we identified and expressed a novel MS membrane protein P35. Sequence similarity showed that P35 was conservative and commonly existed among MS strains. Membrane protein extraction and immunofluorescence assay confirmed that P35 was distributed on the surface of MS. The production of specific antibodies after immunization with recombinant protein rP35 suggested its immunogenicity. The antigenicity of P35 was evaluated from two aspects by using polyantiserum against MS and rP35. Furthermore, in assays to identify the immune peptides of P35, all successfully expressed truncated segments could react with positive polyantiserum of MS, suggesting that P35 had more than one immune peptide. In conclusion, our study successfully identified P35 as a conservative antigen of MS, which may act as a potential candidate for the future development of a vaccine against MS.

Highlights

Mycoplasma synoviae (MS) is an important pathogen in the poultry industry
The genome of the MS WVU1853 strain, obtained from the National Center for Biotechnology Information (NCBI) database, contains 675 protein coding sequences (CDSs). Among these CDSs, Psortb predicted 149 CDSs to be located on the cytoplasmic membrane, 14 CDSs were extracellular, and 227 CDSs were unknown
After analysis with BOMP, LipoP 1.0, and Pfam, we identified that P35 was located on the cell membrane, was not a lipoprotein, and had signal peptide and was selected for further analysis in this study

Summary

Introduction

Mycoplasma synoviae (MS) is an important pathogen in the poultry industry. MS infections rarely cause direct death of chickens, they lead to obvious lameness, growth retardation, lower availability of ketone bodies, lower egg production rate, and higher eggshell apex abnormalities, leading to serious economic losses in the poultry industry [4,5,6]. MS co-infections with other infectious agents such as Newcastle disease virus, Escherichia coli, and Mycoplasma gallisepticum increase economic losses [7,8,9,10]. With the emergence of drug-resistant strains [11,12,13], vaccination is the most effective way to control MS, combined with hygiene and management procedures [14, 15].

Methods

Results

Conclusion