Department of Biology, Biodiversity Research Cluster, Faculty of Science, Mahidol University, Bangkok, Thailand.
Institute of Molecular Biosciences, Mahidol University, Salaya, Nakhon Pathom, Thailand.
PLoS One. 2021 Apr 1;16(4):e0249354. doi: 10.1371/journal.pone.0249354. eCollection 2021.
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.
Q 热是由严格细胞内细菌贝氏柯克斯体引起的最重要的人畜共患病之一。这种细菌感染在人类和动物中都有频繁报道，尤其是反刍动物。蜱是重要的外寄生虫，是类似柯克斯体的内共生体（CLE）的储存宿主。在这项研究中，我们试图从牛路径采集的环状硬蜱中表达 CLE 的伴侣编码基因。已通过大肠杆菌扩增和表达部分 DnaK 编码序列。通过 MS-MS 光谱和 UniProt 数据库分析氨基酸序列。尽管核苷酸序列表明核苷酸变异和多样性很高，但许多核苷酸替换是同义的。此外，氨基酸替换补偿了原始氨基酸的物理化学性质。免疫表位数据库和分析资源（IEDB-AR）用于指示部分 DnaK 蛋白的抗原性，并预测 B 和 T 细胞的表位。有趣的是，一些预测的 MHC-I 中的 HLA-A 和 B 等位基因和属于 MHC-II 的 HLA-DR 等位基因与 Q 热患者中对 C. burnetii 的 T 细胞反应相似。因此，环状硬蜱的 CLE 的部分 DnaK 蛋白可以被认为是一种具有未来前景的疫苗候选物和免疫原性标志物。
