With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L p...With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L proteins has been reported so far. Since detailed knowledge of the protein tertiary structure is required to understand its biological function, a method is needed to determine the structure of these proteins. In this study, the structural data of known mammal MT was used to determine the interatomic distance constraints of the CXC and CXXC motifs and the metal_sulfur chelating cluster. Then several possible MT conformations were predicted using a distance geometry algorithm. The statistical analysis was used to select those with much lower target function values and lower conformation energies as the predicted tertiary structural models of the cysteine_rich (CR) domains of these proteins. A suitable prediction method for modeling the CR domain of the plant MT_L protein was constructed. The accurately predicted result for the known structure of an MT protein from blue crab suggests that this method is practicable. The tertiary structures of CR domains of rape MT_L protein LSC54 was then modeled with this method.展开更多
试验旨在研究猪圆环病毒不同佐剂疫苗的制备及其对免疫原性的影响。将去除信号肽的PCV2(porcine circovirus type 2,PCV2)Cap蛋白基因连接在pET-28a载体上,进行诱导表达,用脱氧胆酸钠(DOC)和低浓度尿素对表达产物进行溶解,制备氢氧化铝...试验旨在研究猪圆环病毒不同佐剂疫苗的制备及其对免疫原性的影响。将去除信号肽的PCV2(porcine circovirus type 2,PCV2)Cap蛋白基因连接在pET-28a载体上,进行诱导表达,用脱氧胆酸钠(DOC)和低浓度尿素对表达产物进行溶解,制备氢氧化铝胶体佐剂、脂质体佐剂、弗氏佐剂、白油佐剂、蜂胶佐剂,并与纯化的PCV2-Cap蛋白混合制成亚单位疫苗,以商品化的灭活疫苗作为阳性对照,免疫小鼠,并使用ELISA方法检测动物血清中抗体及细胞因子含量的变化,评估其免疫保护效果。结果显示,表达产物以包涵体的形式存在,使用DOC溶解包涵体可省略蛋白复性步骤,且纯化方法简单,获得纯度较高的衣壳蛋白;ELISA检测结果表明PCV2-Cap蛋白能诱导产生特异性较高的抗体;水系佐剂制备的亚单位疫苗具有较高的免疫活性,为亚单位疫苗的商品化提供重要的数据支持。展开更多
An analysis using SDS\|PAGE of acidic and basic protein fractions extracted from rice seedling treated with salicylic acid (SA) yielded several new proteins, some of which are similar in relative molecular mass to PR...An analysis using SDS\|PAGE of acidic and basic protein fractions extracted from rice seedling treated with salicylic acid (SA) yielded several new proteins, some of which are similar in relative molecular mass to PR\|1a,c, PR\|2, 2e and PR\|3d, 3e of tobacco. Direct assays for peroxidases and β\|1,3\|glucanases demonstrated that the activities of the two enzymes in the rice seedlings increased rapidly with time after SA treatment, reaching a maximum 6 days after treatment.Disease resistance tests showed that SA treated rice seedlings stunted the development of blight lesions and displayed higher resistance to rice blight pathogen ( Xanthomonas oryzea pv. oryzea ). The data suggest that the treatment with SA, even for plants with high endogenous SA levels such as rice, may induce the appearance of new proteins and the formation of disease resistance. The results contribute to the analysis of the SA role in rice systemic acquired resistance. 展开更多
文摘With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L proteins has been reported so far. Since detailed knowledge of the protein tertiary structure is required to understand its biological function, a method is needed to determine the structure of these proteins. In this study, the structural data of known mammal MT was used to determine the interatomic distance constraints of the CXC and CXXC motifs and the metal_sulfur chelating cluster. Then several possible MT conformations were predicted using a distance geometry algorithm. The statistical analysis was used to select those with much lower target function values and lower conformation energies as the predicted tertiary structural models of the cysteine_rich (CR) domains of these proteins. A suitable prediction method for modeling the CR domain of the plant MT_L protein was constructed. The accurately predicted result for the known structure of an MT protein from blue crab suggests that this method is practicable. The tertiary structures of CR domains of rape MT_L protein LSC54 was then modeled with this method.
文摘试验旨在研究猪圆环病毒不同佐剂疫苗的制备及其对免疫原性的影响。将去除信号肽的PCV2(porcine circovirus type 2,PCV2)Cap蛋白基因连接在pET-28a载体上,进行诱导表达,用脱氧胆酸钠(DOC)和低浓度尿素对表达产物进行溶解,制备氢氧化铝胶体佐剂、脂质体佐剂、弗氏佐剂、白油佐剂、蜂胶佐剂,并与纯化的PCV2-Cap蛋白混合制成亚单位疫苗,以商品化的灭活疫苗作为阳性对照,免疫小鼠,并使用ELISA方法检测动物血清中抗体及细胞因子含量的变化,评估其免疫保护效果。结果显示,表达产物以包涵体的形式存在,使用DOC溶解包涵体可省略蛋白复性步骤,且纯化方法简单,获得纯度较高的衣壳蛋白;ELISA检测结果表明PCV2-Cap蛋白能诱导产生特异性较高的抗体;水系佐剂制备的亚单位疫苗具有较高的免疫活性,为亚单位疫苗的商品化提供重要的数据支持。
基金the National Natural Science Foundation of China! (No. 39780 0 30 ) Trans-Century Training Programme Foundation for Talen
文摘An analysis using SDS\|PAGE of acidic and basic protein fractions extracted from rice seedling treated with salicylic acid (SA) yielded several new proteins, some of which are similar in relative molecular mass to PR\|1a,c, PR\|2, 2e and PR\|3d, 3e of tobacco. Direct assays for peroxidases and β\|1,3\|glucanases demonstrated that the activities of the two enzymes in the rice seedlings increased rapidly with time after SA treatment, reaching a maximum 6 days after treatment.Disease resistance tests showed that SA treated rice seedlings stunted the development of blight lesions and displayed higher resistance to rice blight pathogen ( Xanthomonas oryzea pv. oryzea ). The data suggest that the treatment with SA, even for plants with high endogenous SA levels such as rice, may induce the appearance of new proteins and the formation of disease resistance. The results contribute to the analysis of the SA role in rice systemic acquired resistance.
