Introduction::Toxoplasmosis is one of the most common parasitic infections
transmitted between humans and animals, caused by the protozoan Toxoplasma gondii.
This organism acts as an obligate intracellular parasite, presenting an active and rapidly
proliferating form known as a tachyzoite, in addition to two durable forms: the tissue
cyst and the oocyst. Due to the considerable global impact of chronic infections in
various host species, especially in humans and domestic animals, creating and
producing an effective vaccine for preventing and managing toxoplasmosis is critically
essential. The excretory antigens of Toxoplasma gondii play a vital role in vaccine
development and diagnostic processes, with the SAG2 antigen being particularly
significant. At present, sophisticated bioinformatics tools are utilized to design efficient
signal peptides. This research will adopt an in silico approach to evaluating different
signal peptides.
Methods::The signal peptide sequence was obtained from the Signal Peptide website
and Uniprot. Following this, SignalP was utilized to predict the signal peptides and
determine the positions of their cleavage sites. The ProtProm tool was then employed to
assess the physicochemical characteristics and solubility. Furthermore, ProtCompB was
used to forecast the subcellular localization of the fusion protein.
Results::Of the 50 signal peptides analyzed, 49 were excluded based on SignalP criteria.
The signal peptide with the highest aliphatic index was HDEA_ECOLI, while
TORT_ECOLI exhibited the highest GRAVY value.
Discussion::Additionally, SAG2, when fused with all signal peptides, was explicitly
designed for the Sec pathway, except NAPA_ECOLI, MBHT_ECOLI, CUEO_ECOLI,
and OPGD_ECOLI.
Conclusion::An appropriate signal peptide was recognized for the fusion and
translocation of SAG2 into the extracellular environment. While additional experimental
studies are necessary for conclusive validation.
