Vet World Vol.16 September-2023 Article-3
Research Article
Veterinary World, 16(9): 1790-1795
https://doi.org/10.14202/vetworld.2023.1790-1795
Recombinant Salmonella enterica OmpX protein expression and its potential for serologically diagnosing Salmonella abortion in mares
2. Department of Veterinary Medicine, Faculty of Veterinary and Animal Husbandry Technology, S. Seifullin Kazakh Agrotechnical Research University, 010000, Astana, Kazakhstan.
3. Laboratory of Immunochemistry and Immunobiotechnology, National Center for Biotechnology, 010000, Astana, Kazakhstan.
4. Research Platform of Agricultural Biotechnology, S. Seifullin Kazakh Agrotechnical Research University, 010011, Astana, Kazakhstan.
Background and Aim: Salmonella abortion in mares is caused by Salmonella enterica subspecies enterica serovar abortus equi infection and is characterized by premature (abortion) or non-viable fetus birth. Although all horses are susceptible to infection, the condition is more often clinically manifested in pregnant mares, with most abortions recorded in young females. In addition, nonspecific clinical disease signs and poorly sensitive and effective bacteriological diagnostic methods hinder rapid and reliable infection diagnoses. Immunochemical methods such as enzyme-linked immunosorbent assay (ELISA) and immunochromatography assays can facilitate effective and rapid diagnoses. However, they require highly specific and active antigens and antibodies. This study aimed to generate a recombinant S. enterica outer membrane protein X (OmpX) and evaluate its suitability for serological diagnosis of Salmonella abortion in mares.
Materials and Methods: Outer membrane protein X from the S. enterica antigen was synthesized de novo and expressed in Escherichia coli using the pET28 vector. Transformed E. coli cells were cultured under different conditions to detect recombinant OmpX (rOmpX) expression, and rOmpX purification and refolding were both conducted using metal affinity chromatography. Refolded and purified rOmpX was characterized by western blotting, liquid chromatography with tandem mass spectrometry, and ELISA.
Results: After optimized rOmpX expression, a 23 kDa molecular weight protein was identified. Amino acid sequence analysis using Mascot program suggested that these peptides were the OmpX protein from S. enterica. High specificity and diagnostic efficiency were recorded when rOmpX was used in ELISA against 89 serum samples from aborted and contact mares.
Conclusion: Recombinant outer membrane protein, in comparison to the O antigen, demonstrated better diagnostic characteristics against sera from mares who aborted and contact horses. Keywords: diagnostics, outer membrane proteins, recombinant antigens, Salmonella abortion in mares, Salmonella enterica, specific antibodies.
Keywords: diagnostics, outer membrane proteins, recombinant antigens, Salmonella abortion in mares, Salmonella enterica, specific antibodies.
How to cite this article: Borovikov S, Ryskeldina A, Tursunov K, Syzdykova A, and Akibekov O (2023) Recombinant Salmonella enterica OmpX protein expression and its potential for serologically diagnosing Salmonella abortion in mares, Veterinary World, 16(9): 1790-1795.
Received: 06-04-2023 Accepted: 08-08-2023 Published online: 13-09-2023
Corresponding author: Sergey Borovikov E-mail: nicsb_katu@mail.ru
DOI: 10.14202/vetworld.2023.1790-1795
Copyright: Borovikov, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.