The SAG1 is a tachyzoite-specific protein critical for Toxoplasma gondii (T. gondii) adhesion to surface receptors of the host cells. In this study we've comprehensively excavated the sequence of SAG1 using online bioinformatics servers toward better vaccine design against toxoplasmosis. Web-based tools were used to assess the physico-chemical properties, post-translational modifications (PTMs), transmembrane domains, subcellular localization, secondary and 3D structures, as well as B-cell, Cytotoxic T cells (CTL) and major histocompatibility complex (MHC) epitopes. The 336 amino acid sequence possessed a molecular weight of 34829.02 D, aliphatic index of 80.15 and GRAVY score of 0.129. There was 47 PTM sites without any transmembrane domains. Also, the SAG1 protein was appointed to be immunogen and non-allergen. The secondary structure comprised 62.5% random coil, 26.79% extended strand and 10.71% alpha helix. Ramachandran plot of the refined model demonstrated 94.4% residues in the favored region, 4.8% in allowed region and 0.8% in outlier region. Additionally, various potential B-cell (linear and conformational), CTL and HTL epitopes were predicted for T. gondii SAG1. This in silico investigation would be a premise for appropriate immunization strategies against toxoplasmosis. More studies are anticipated to be done empirically using SAG1 immunoprotective epitopes combined with other antigenic compounds.

SAG1是一种对弓形虫（T. gondii）至关重要的速殖子特异性蛋白）粘附于宿主细胞的表面受体。在这项研究中，我们已经使用在线生物信息服务器全面挖掘了SAG1的序列，以更好地设计抗弓形虫病的疫苗。使用基于Web的工具评估理化特性，翻译后修饰（PTM），跨膜结构域，亚细胞定位，二级和3D结构以及B细胞，细胞毒性T细胞（CTL）和主要组织相容性复合物（MHC）表位。336个氨基酸序列的分子量为34829.02D，脂族指数为80.15，GRAVY得分为0.129。有47个PTM位点，没有任何跨膜结构域。同样，SAG1蛋白被指定为免疫原和非过敏原。二级结构包括62.5％的无规卷曲，26.79％的延伸链和10.71％的α螺旋。精炼模型的Ramachandran图显示，在有利区域中残留94.4％，在允许区域中残留4.8％，在异常区域中残留0.8％。此外，预测了各种潜在的B细胞（线性和构象），CTL和HTL表位弓形虫TAG 1。这项计算机调查将为针对弓形虫病的适当免疫策略提供前提。预计将使用SAG1免疫保护性抗原表位与其他抗原性化合物结合进行经验研究。