Bioinformatic analysis and prokaryotic expression of RmS-15 from Rhipicephalus microplus
- Author:
XU Yuexia
;
FAN Jieli
;
LIANG Dejuan
;
CHEN Huaqing
;
ZHAO Jianguo
;
GUAN Qingfeng
- Publication Type:Journal Article
- Keywords:
Rhipicephalus microplus;
RmS-15;
bioinformatics analysis;
prokaryotic expression;
vaccine
- From:
China Tropical Medicine
2023;23(12):1276-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the biological characteristics of the serine protease inhibitor 15 (RmS-15) protein of Rhipicephalus microplus, and to perform molecular cloning and prokaryotic expression. Methods RmS-15 gene was amplified and sequenced to construct a phylogenetic tree to understand its evolutionary relationships. Bioinformatic tools were used to analyze the physicochemical properties, signal peptide, secondary and tertiary structure of the RmS-15 protein. In addition, DNA star and ABCpred were used to predict potential B-lymphocyte antigenic epitopes of RmS-15 protein, and potential T-lymphocyte antigenic epitopes were predicted by SYF-PEITHI and IEDB. Finally, the RmS-15 recombinant protein of Rhipicephalus microplus was obtained using the E.coli prokaryotic expression system and purified. Results The RmS-15 gene with 1 212 bp was successfully amplified, encoding a protein comprising 403 amino acids. Phylogenetic tree results indicated high conservation of the RmS-15 protein among different tick amino acid sequences, with the closest phylogenetic relationships to the Rhipicephalus haemaphysaloides and the Rhipicephalus sanguineus. The results of physicochemical property analysis showed a 20-amino acid signal peptide at the N-terminus of the RmS-15 protein, with a relative molecular weight and theoretical isoelectric point of 44 000 and 6.68, respectively. The protein showed an average hydrophilicity of 0.001, classifying it as a stably hydrophilic protein. The results of antigenicity analysis showed that the dominant fragments of B-cell antigenic epitopes of RmS-15 protein were 102-112 aa,147-152 aa and 207-215 aa, and the dominant fragments of T-cell antigenic epitopes were 3-11 aa, 6-14 aa, 27-33 aa, 34-37 aa. Protein expression results showed that RmS-15 protein exhibited high expression levels in the supernatant after induction with 0.8 mmol/L IPTG at 16 ℃ for 24 hours and reached a successful purification with a single band of the protein molecular weight of 44 000. Conclusions The method of prokaryotic expression and purification of RmS-15 protein from Rhipicephalus microplus was successfully established. Bioinformatics analysis demonstrated its strong antigenicity, suggesting its potential to develop as a candidate vaccine for ticks.
- Full text:20241223165836782437.Bioinformatic analysis and prokaryotic expression of RmS-15 from Rhipicephalus microplus.pdf
