Bioinformatic evaluation of ClpP as a vaccine target in Streptococcus pneumoniae

To conduct a comprehensive bioinformatic analysis to assess the immunogenicity and conservation profiles of ClpP in Streptococcus pneumoniae, thereby verifying its feasibility as a candidate vaccine target.

The nucleotide and amino acid sequences of the clpP gene were obtained from the NCBI database. The fundamental characterizations of ClpP were retrieved from the public database PneumoWiki. NetPhos was used to predict phosphorylation sites, whereas SOPMA, Swiss-Model and STRING were employed to analyze secondary/tertiary structures and functional interaction network, respectively. Antigenic epitope mapping was carried out using DNASTAR, SYFPEITHI, NetMHCIIpan 4.0 and NetMHC. Multiple sequence alignment (MSA) was performed using Jalview software to analyze the conservation of the predicted epitopes across S. pneumoniae strains. Concurrently, a phylogenetic tree was constructed to evaluate the cross-species conservation of the ClpP protein.

ClpP (196 aa, pI 4.74) showed high hydrophobicity and without signal peptides/transmembrane domains. Phosphorylation sites (Ser/Thr/Tyr) were identified. The secondary structure of ClpP consists of 94 α-helices, 37 β-strands and 65 random coils. The functional interaction network of ClpP involves 10 interacting partners. Immunoinformatic analysis further detected immunodominant B-cell and T-cell epitopes within the ClpP sequence.

Taken together, these data suggest that ClpP exhibits robust immunogenicity and multiple antigenic epitopes, supporting its potential as a peptide-based vaccine candidate against S. pneumoniae.