萝卜磷脂氢谷胱甘肽过氧化物酶(RsPHGPx)是一个定位于线粒体的蛋白质.为了阐明该蛋白质线粒体定位信号的准确切割位点,采用了免疫亲和层析方法纯化天然的RsPHGPx.用重组RsPHGPx 蛋白免疫兔子获得了抗RsPHGPx 的多克隆抗血清,以重组RsPH ...萝卜磷脂氢谷胱甘肽过氧化物酶(RsPHGPx)是一个定位于线粒体的蛋白质.为了阐明该蛋白质线粒体定位信号的准确切割位点,采用了免疫亲和层析方法纯化天然的RsPHGPx.用重组RsPHGPx 蛋白免疫兔子获得了抗RsPHGPx 的多克隆抗血清,以重组RsPH G Px 蛋白为配体,采用亲和层析技术对抗血清进行了纯化,得到了单特异性的抗RsPHGPx 的抗体.将纯化好的抗体偶联到一个N-羟基琥珀酰亚胺(NHS)预先激活的琼脂糖柱子上,装配成一个以单特异性的抗RsPHGPx 抗体为配体的免疫亲和层析柱.经过对纯化条件的摸索和优化,形成了一个简单、特异的一步法纯化方案.按照该方案,从萝卜幼苗线粒体总蛋白质提取物中纯化到一个分子质量与预期值相一致的特异蛋白质.免疫印迹分析表明,该蛋白质被抗RsPH G Px 的抗血清特异识别.酶活性分析表明,该蛋白质具有显著的PH G Px 活性.这些结果表明,纯化到的特异蛋白质是萝卜的RsPH G Px天然蛋白.这是首个关于定位于植物细胞器的PH G Px 蛋白纯化的报道.这一结果为准确测定RsPH G Px 信号肽的切割位点奠定了基础,并将有助于对植物PH G Px 的亚细胞定位机制及其生理功能的深入研究.展开更多
The only difference of primary structure between single-chain prourokinase (pro-UK or scu-PA) and two-chain urokinase (UK or tcu-PA) is the cleavage of a single peptide bond (Lys158-Ile159) and transform scu-PA into i...The only difference of primary structure between single-chain prourokinase (pro-UK or scu-PA) and two-chain urokinase (UK or tcu-PA) is the cleavage of a single peptide bond (Lys158-Ile159) and transform scu-PA into its active two-chain form. A 13-peptide (Thr-Leu-Arg-Pro-Arg-Phe-Lys-Ile-Ile-Gly- Gly-Glu-Cys), which spans the cleavage peptide bond, was synthesized and linked to KLH (Keyhole limpet hemocyanin). The Balb/c mice were immunized by the conjugated protein with proper adjuvant. According to the Kohler and Milstein’s methods, a hybridoma cell line G7 secreting monoclonal antibody specific for scu-PA was obtained. The anti-scu-PA McAb, purified from the supernatant of porous microcarrier hybridoma cell culture, was conjugated to CNBr-activated Sepharose 4B to prepare an immuno-affinity chromatography column. The u-PA was purified only by this affinity column from the supernatant of cultivating the u-PA-producing recombinant CHO cell, the u-PA recovery ratio is 90.4%, the purification factor was about 50, with the specific activity of 1.2×10 5IU/mg, the scu-PA ratio in the u-PA product was 96.3%. Compared to immuno-affinity chromatography, the 3-step process for purifying u-PA (cation-exchange co-lumn, gel filtration column and benzamidine affinity column)has a u-PA recovery ratio of about 65%, with a specific activity of 1.0×10 5IU/mg, and an scu-PA ratio of about 90%. These results showed that immuno-affinity chromatography is simple to recover u-PA and effective to separate scu-PA from tcu-PA.展开更多
文摘萝卜磷脂氢谷胱甘肽过氧化物酶(RsPHGPx)是一个定位于线粒体的蛋白质.为了阐明该蛋白质线粒体定位信号的准确切割位点,采用了免疫亲和层析方法纯化天然的RsPHGPx.用重组RsPHGPx 蛋白免疫兔子获得了抗RsPHGPx 的多克隆抗血清,以重组RsPH G Px 蛋白为配体,采用亲和层析技术对抗血清进行了纯化,得到了单特异性的抗RsPHGPx 的抗体.将纯化好的抗体偶联到一个N-羟基琥珀酰亚胺(NHS)预先激活的琼脂糖柱子上,装配成一个以单特异性的抗RsPHGPx 抗体为配体的免疫亲和层析柱.经过对纯化条件的摸索和优化,形成了一个简单、特异的一步法纯化方案.按照该方案,从萝卜幼苗线粒体总蛋白质提取物中纯化到一个分子质量与预期值相一致的特异蛋白质.免疫印迹分析表明,该蛋白质被抗RsPH G Px 的抗血清特异识别.酶活性分析表明,该蛋白质具有显著的PH G Px 活性.这些结果表明,纯化到的特异蛋白质是萝卜的RsPH G Px天然蛋白.这是首个关于定位于植物细胞器的PH G Px 蛋白纯化的报道.这一结果为准确测定RsPH G Px 信号肽的切割位点奠定了基础,并将有助于对植物PH G Px 的亚细胞定位机制及其生理功能的深入研究.
文摘The only difference of primary structure between single-chain prourokinase (pro-UK or scu-PA) and two-chain urokinase (UK or tcu-PA) is the cleavage of a single peptide bond (Lys158-Ile159) and transform scu-PA into its active two-chain form. A 13-peptide (Thr-Leu-Arg-Pro-Arg-Phe-Lys-Ile-Ile-Gly- Gly-Glu-Cys), which spans the cleavage peptide bond, was synthesized and linked to KLH (Keyhole limpet hemocyanin). The Balb/c mice were immunized by the conjugated protein with proper adjuvant. According to the Kohler and Milstein’s methods, a hybridoma cell line G7 secreting monoclonal antibody specific for scu-PA was obtained. The anti-scu-PA McAb, purified from the supernatant of porous microcarrier hybridoma cell culture, was conjugated to CNBr-activated Sepharose 4B to prepare an immuno-affinity chromatography column. The u-PA was purified only by this affinity column from the supernatant of cultivating the u-PA-producing recombinant CHO cell, the u-PA recovery ratio is 90.4%, the purification factor was about 50, with the specific activity of 1.2×10 5IU/mg, the scu-PA ratio in the u-PA product was 96.3%. Compared to immuno-affinity chromatography, the 3-step process for purifying u-PA (cation-exchange co-lumn, gel filtration column and benzamidine affinity column)has a u-PA recovery ratio of about 65%, with a specific activity of 1.0×10 5IU/mg, and an scu-PA ratio of about 90%. These results showed that immuno-affinity chromatography is simple to recover u-PA and effective to separate scu-PA from tcu-PA.
