结核分枝杆菌 PPE58 蛋白的结构及功能分析OA

Objective To explore the physicochemical properties,structure and function of Mycobacterium tuberculosis protein PPE58 by bioinformatics analysis technology,so as to lay a foundation for the follow-up study of anti-tuberculosis vaccine.Methods The amino acid sequence of PPE58 protein was obtained from NCBI.The open reading frame,physicochemical properties,hydrophobicity,subcellular localization,signal peptide,transmembrane region,O-glycosylation site,phosphorylation site and N-acetylation site of PPE58 protein were analyzed by bioinformatics software.The secondary and tertiary structures,B cell epitopes,T cell epitopes and PPE58 interacting proteins of PPE58 protein were analyzed.Results The protein was composed of 232 amino acid residues,and its corresponding coding gene Rv3426 had a total length of 699 bp and contained four open reading frames.PPE58 was identified as hydrophilic and had no transmembrane region.Its theoretical molecular weight was calculated to be 25 872.53,isoelectric point was 9.66,and instability index was 47.3.In addition,the protein molecule carries 23 phosphorylation modification sites and 1 N-glycosylation site.The PPE58 protein contains 121 α-helices,11 β-sheets,92 random coils and 8 β-turns.Four major B cell epitopes were predicted by IEDB tool.Further comprehensive evaluation by SYFPEITHI and other tools found that PPE58 protein has multiple T cell epitopes and has potential binding ability with a variety of MHC-Ⅰ and MHC-Ⅱ molecules.Conclusion PPE58 is a hydrophilic protein with abundant T and B cell epitopes,which can be used as a candidate antigen for tuberculosis vaccine research.