目的对肠出血性大肠埃希菌O157:H7紧密黏附素C300与黏膜佐剂不耐热肠毒素(LTB)融合蛋白二级结构及B细胞识别表位进行预测,为开发新型疫苗提供理论依据.方法采用DNA star软件中的Protean预测软件对Intim in C300与LTB融合蛋白的亲水...目的对肠出血性大肠埃希菌O157:H7紧密黏附素C300与黏膜佐剂不耐热肠毒素(LTB)融合蛋白二级结构及B细胞识别表位进行预测,为开发新型疫苗提供理论依据.方法采用DNA star软件中的Protean预测软件对Intim in C300与LTB融合蛋白的亲水性指数、β-转角、柔韧性、表面可及性和抗原指数进行预测.结果在融合蛋白N端第1-10、20-30、110-120、210-220、300-310、350-360、380-390和415-420区段可能是α-螺旋中心,在N端第195-205、300-320、335-350和390-410区段形成4个大的β-折叠中心区域,在各β-折叠区间存在均匀且较丰富的转角区域.融合蛋白的蛋白柔性区域可能位于N端第20-35、52-65、75-85、105-115、150-160、172-188、260-275和372-388区域,这些区域有一定幅度的折叠或摆动,可形成较复杂的三级结构.亲水性区域位于第50-60、70-80、155-165、190-200、240-250、260-270、330-340和375-385区段,这8个区域作为抗原表位可能性大.结论通过生物信息学技术分析,可有效地预测融合蛋白二级结构和B细胞表位,为人工合成优势肽段进行肠出血性大肠埃希菌O157:H7的重组疫苗研制提供理论依据.展开更多
P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (Hear...P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (HearNPV),and the identification of their recognition epitopes.The full-length P74,without the transmembrane domains at the C-terminus,was first divided into three segments (N,M and C,respectively),based on the proposed cleavage model for the protein,which were then expressed individually.Western blot analyses revealed specific cross-reactions with the N fragment,for both 20D9 and 21E1.Extensive truncation,followed by prokaryotic expression,of the P74 N fragment was then performed in order to screen for linear epitopes of P74.The recognition regions of 20D9 and 21E1 were revealed to be localized at R144-T153 and T199-C219,respectively.In addition,immunofluorescence microscopy indicated that 20D9 and 20F9 could recognize native P74 in HearNPV-infected cells.These findings will facilitate further investigations of the proteolytic processing of HearNPV P74,and of its involvement in virus-host interactions.展开更多
文摘目的对肠出血性大肠埃希菌O157:H7紧密黏附素C300与黏膜佐剂不耐热肠毒素(LTB)融合蛋白二级结构及B细胞识别表位进行预测,为开发新型疫苗提供理论依据.方法采用DNA star软件中的Protean预测软件对Intim in C300与LTB融合蛋白的亲水性指数、β-转角、柔韧性、表面可及性和抗原指数进行预测.结果在融合蛋白N端第1-10、20-30、110-120、210-220、300-310、350-360、380-390和415-420区段可能是α-螺旋中心,在N端第195-205、300-320、335-350和390-410区段形成4个大的β-折叠中心区域,在各β-折叠区间存在均匀且较丰富的转角区域.融合蛋白的蛋白柔性区域可能位于N端第20-35、52-65、75-85、105-115、150-160、172-188、260-275和372-388区域,这些区域有一定幅度的折叠或摆动,可形成较复杂的三级结构.亲水性区域位于第50-60、70-80、155-165、190-200、240-250、260-270、330-340和375-385区段,这8个区域作为抗原表位可能性大.结论通过生物信息学技术分析,可有效地预测融合蛋白二级结构和B细胞表位,为人工合成优势肽段进行肠出血性大肠埃希菌O157:H7的重组疫苗研制提供理论依据.
基金supported by the National Science Foundation of China(31130058 to Z.H.).Monoclonal Antibodies against HearNPV P74
文摘P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (HearNPV),and the identification of their recognition epitopes.The full-length P74,without the transmembrane domains at the C-terminus,was first divided into three segments (N,M and C,respectively),based on the proposed cleavage model for the protein,which were then expressed individually.Western blot analyses revealed specific cross-reactions with the N fragment,for both 20D9 and 21E1.Extensive truncation,followed by prokaryotic expression,of the P74 N fragment was then performed in order to screen for linear epitopes of P74.The recognition regions of 20D9 and 21E1 were revealed to be localized at R144-T153 and T199-C219,respectively.In addition,immunofluorescence microscopy indicated that 20D9 and 20F9 could recognize native P74 in HearNPV-infected cells.These findings will facilitate further investigations of the proteolytic processing of HearNPV P74,and of its involvement in virus-host interactions.