Preliminary study on the function of Toxoplasma gondii α-amylase 1 and its protective immunity against acute and chronic toxoplasmosis
作者单位：State Key Laboratory of Agricultural MicrobiologyCollege of Veterinary MedicineHuazhong Agricultural University
会议名称：《中国畜牧兽医学会兽医寄生虫学分会第一届青年科学家学术论坛》
会议日期：2019年
学科分类：090601[农学-基础兽医学] 09[农学] 0906[农学-兽医学]
基 金：supported by the National Natural Science Foundation of China(Grant No.31572510)
关 键 词：Toxoplasma gondii α-amylase 1 amylopectin metabolism protection vaccine
摘 要：As a vitalparasiticprotozoan,the energy metabolism of Toxoplasma gondii(***)bradyzoitesis different from tachyzoites,and the most typical feature is massive amylopectin accumulated in the cytoplasm of *** is supposed that the amylopectin granule may be an energy reserve for the transformation of cysts and oocysts into tachyzoites.a-amylase 1(a-amyl) is one of the enzymes involved in the digestion of the amylopectin,and may be phosphorylated by *** the present study,ME49△α-amy1 mutant was generated using CRISPR/CAS9-mediated homologous gene replacement system to explore the specific biological functions of a-amyl in amylopectin metabolic pathway,and then intracellular replication assay and plaque assay were used to measure the proliferation ability of tachyzoites in *** staining was performed to identify the starch synthesis of ME49△α-amy1 mutant,and the virulence and formation of brain cysts formation were *** results obtained from our study revealed that the deletion of the a-amyl gene had no significant effect on the reproduction and starch synthesis in vitro,but contributed to virulence attenuation and reduction of the formation of brain cysts in ***,a mouse model was established to explore the protective immunity of ME49△α-awy1 mutant,and demonstrated that ME49△α-amy1 mutant could provide short-term and long-term protection against acute and chronic infections that survival rates were nearly 100%.From the experimental results,it can be assumed that other enzymes in combination with a-amyl may be involved in digestion of the amylopectin,and ME49△α-amyl attenuated strain exert a superior protective effect on both acute and chronic infections,suggesting that ME49 Aa-amyl mutant may possess the possibility of potential vaccine candidate for toxoplasmosis.