Partial DnaK protein expression from Coxiella-like endosymbiont of Rhipicephalus annulatus tick

Abstract

Q fever is one of the most important zoonotic diseases caused by the obligate intracellular bacteria, Coxiella burnetii. This bacterial infection has been frequently reported in both humans and animals, especially ruminants. Ticks are important ectoparasite and serve as reservoir hosts of Coxiella-like endosymbionts (CLEs). In this study, we have attempted to express chaperone-coding genes from CLEs of Rhipicephalus annulatus ticks collected fromcow path. The partial DnaK coding sequence has been amplified and expressed by Escherichia coli. Amino acid sequences have been analyzed by MS-MS spectrometry and the UniProt database. Despites nucleotide sequences indicating high nucleotide variation and diversity, many nucleotide substitutions are synonymous. In addition, amino acid substitutions compensate for the physicochemical properties of the original amino acids. Immune Epitope Database and Analysis Resource (IEDB-AR) was employed to indicate the antigenicity of the partial DnaK protein and predict the epitopes of B-and T-cells. Interestingly, some predicted HLA-A and B alleles of the MHC-I and HLA-DR alleles belonging to MHC-II were similar to T-cell responses to C. burnetii in Q fever patients. Therefore, the partial DnaK protein of CLE from R. annulatus could be considered a vaccine candidate and immunogenic marker with future prospects.

Recent Advances on the Innate Immune Response to Coxiella burnetii

“…effective and safe vaccines against Q fever (Gerlach et al, 2017;Reeves et al, 2017;Jaydari et al, 2020;Long et al, 2021;Nooroong et al, 2021;Piel et al, 2021).…”

“…Additionally, new immunodiagnostic assays, such as IGRA, could become more appreciable tools to diagnose past C. burnetii infections and they may result very helpful especially in the context of pre-vaccination screens. The application of latest omics, genetic, and in silico technologies for the identification of conserved T-cell epitopes in multiple host species, the development of genetically modified organisms, and the design of multi-epitope antigens are promising approaches for collaborative integration in the development of more effective and safe vaccines against Q fever ( Gerlach et al., 2017 ; Reeves et al., 2017 ; Jaydari et al., 2020 ; Long et al., 2021 ; Nooroong et al., 2021 ; Piel et al., 2021 ).…”