依赖叶黄素循环的热耗散是一种主要防御光破坏的机制。参与叶黄素循环的酶是紫黄质脱环氧化酶和玉米黄质环氧化酶 ,紫黄质脱环氧化酶已分离纯化 ,其 c DNA已被克隆 ,其活性主要受跨类囊体膜的 p H梯度和抗坏血酸浓度的调节 ;玉米黄质环...依赖叶黄素循环的热耗散是一种主要防御光破坏的机制。参与叶黄素循环的酶是紫黄质脱环氧化酶和玉米黄质环氧化酶 ,紫黄质脱环氧化酶已分离纯化 ,其 c DNA已被克隆 ,其活性主要受跨类囊体膜的 p H梯度和抗坏血酸浓度的调节 ;玉米黄质环氧化酶还没有被分离出来 ,但其 c DNA也已被克隆 ;其活性主要与NADPH的浓度、O2 及光等有关。展开更多
为了阐明籼稻(Oryza sativa L. spp. indica)、粳稻(O. sativa L. spp. japonica)对低温强光敏感性的差异,着重研究了低温强光下水稻类囊体膜脂不饱和度与叶黄素循环的变化。随着低温强光处理时间的延长,类囊体膜脂不饱和脂肪酸含量降低...为了阐明籼稻(Oryza sativa L. spp. indica)、粳稻(O. sativa L. spp. japonica)对低温强光敏感性的差异,着重研究了低温强光下水稻类囊体膜脂不饱和度与叶黄素循环的变化。随着低温强光处理时间的延长,类囊体膜脂不饱和脂肪酸含量降低,饱和脂肪酸含量增加,因而膜脂不饱和指数(IUFA)下降。同时,叶黄素循环的关键酶——紫黄质脱环氧化酶(VDE)活性降低,叶黄素循环组分中紫黄质(V)含量增加,而单环氧玉米黄质(A)和玉米黄质(Z)的含量减少,表现为(A+Z)/(A+Z+V)比值下降。Arrhenius分析证明,VDE对低温和膜脂不饱和度都敏感。相关分析表明,类囊体IUFA分别与VDE活性、(A+Z)/(A+Z+V)和D1蛋白量呈显著的正相关。与粳稻9516相比,籼稻汕优63类囊体膜的IUFA较低,低温下类囊体膜脂流动性和稳定性较差,VDE活性和(A+Z)/(A+Z+V)比值较低。展开更多
The violaxanthin de-epoxidase gene was cloned from rice (Oryza sativa subsp. japonica). The full length of the cDNA is 1887 bp, encoding a 446-amino acids protein with the transit peptide of 98 amino acids. The bacter...The violaxanthin de-epoxidase gene was cloned from rice (Oryza sativa subsp. japonica). The full length of the cDNA is 1887 bp, encoding a 446-amino acids protein with the transit peptide of 98 amino acids. The bacterial expression vector pET-Rvde was constructed and the expression quantity of the exogenous protein increased with the induction time by 0.4 mmol/L IPTG. Its molecular weight was similar with that of the native VDE. Western blotting indicated that the expressed protein has immu-nological reaction with the VDE polyclonal antibody. The absorbance spectrum together with xanthophyll pigments quantification by HPLC demonstrated that the expressed VDE has its enzyme activity, which can de-epoxidate violaxanthin into antheraxanthin and zeaxanthin in vitro.展开更多
为建立辣椒叶片中新黄质和紫黄质组分分离及含量测定的高效液相色谱检测方法,为辣椒品种耐性的研究提供方法依据。以KOH-甲醇溶液为皂化液,对其质量浓度、体积、皂化温度、皂化时间进行筛选,对提取溶剂、提取溶剂用量以及流动相、柱温...为建立辣椒叶片中新黄质和紫黄质组分分离及含量测定的高效液相色谱检测方法,为辣椒品种耐性的研究提供方法依据。以KOH-甲醇溶液为皂化液,对其质量浓度、体积、皂化温度、皂化时间进行筛选,对提取溶剂、提取溶剂用量以及流动相、柱温、流速等色谱条件进行筛选,确定最佳提取工艺及检测条件。结果表明:建立以10 m L 80%丙酮为提取溶剂、以6 m L 200 g/L的KOH-甲醇溶液为皂化液,50℃皂化30 min为皂化条件的提取工艺;以C18(250 mm×4.6 mm,5μm)色谱柱,流动相为A.乙腈,B.乙酸乙酯,C.水,波长440nm,流速1 m L/min,柱温35℃为色谱检测条件的高效液相色谱检测方法。外标法进行定量,新黄质、紫黄质标准曲线线性关系良好,相关系数为0.998 9和0.998 7,方法平均回收率>70%,方法符合色谱检测要求,可用于辣椒叶片中新黄质、紫黄质含量检测。展开更多
文摘依赖叶黄素循环的热耗散是一种主要防御光破坏的机制。参与叶黄素循环的酶是紫黄质脱环氧化酶和玉米黄质环氧化酶 ,紫黄质脱环氧化酶已分离纯化 ,其 c DNA已被克隆 ,其活性主要受跨类囊体膜的 p H梯度和抗坏血酸浓度的调节 ;玉米黄质环氧化酶还没有被分离出来 ,但其 c DNA也已被克隆 ;其活性主要与NADPH的浓度、O2 及光等有关。
文摘为了阐明籼稻(Oryza sativa L. spp. indica)、粳稻(O. sativa L. spp. japonica)对低温强光敏感性的差异,着重研究了低温强光下水稻类囊体膜脂不饱和度与叶黄素循环的变化。随着低温强光处理时间的延长,类囊体膜脂不饱和脂肪酸含量降低,饱和脂肪酸含量增加,因而膜脂不饱和指数(IUFA)下降。同时,叶黄素循环的关键酶——紫黄质脱环氧化酶(VDE)活性降低,叶黄素循环组分中紫黄质(V)含量增加,而单环氧玉米黄质(A)和玉米黄质(Z)的含量减少,表现为(A+Z)/(A+Z+V)比值下降。Arrhenius分析证明,VDE对低温和膜脂不饱和度都敏感。相关分析表明,类囊体IUFA分别与VDE活性、(A+Z)/(A+Z+V)和D1蛋白量呈显著的正相关。与粳稻9516相比,籼稻汕优63类囊体膜的IUFA较低,低温下类囊体膜脂流动性和稳定性较差,VDE活性和(A+Z)/(A+Z+V)比值较低。
基金This work was supported by the State Key Basic Research Development Plan of China (Grant No. 1998010100)the Innovation Foundation of Laboratory of Photosynthesis Basic Research, Institute of Botany, the Chinese Academy of Sciences.
文摘The violaxanthin de-epoxidase gene was cloned from rice (Oryza sativa subsp. japonica). The full length of the cDNA is 1887 bp, encoding a 446-amino acids protein with the transit peptide of 98 amino acids. The bacterial expression vector pET-Rvde was constructed and the expression quantity of the exogenous protein increased with the induction time by 0.4 mmol/L IPTG. Its molecular weight was similar with that of the native VDE. Western blotting indicated that the expressed protein has immu-nological reaction with the VDE polyclonal antibody. The absorbance spectrum together with xanthophyll pigments quantification by HPLC demonstrated that the expressed VDE has its enzyme activity, which can de-epoxidate violaxanthin into antheraxanthin and zeaxanthin in vitro.
文摘为建立辣椒叶片中新黄质和紫黄质组分分离及含量测定的高效液相色谱检测方法,为辣椒品种耐性的研究提供方法依据。以KOH-甲醇溶液为皂化液,对其质量浓度、体积、皂化温度、皂化时间进行筛选,对提取溶剂、提取溶剂用量以及流动相、柱温、流速等色谱条件进行筛选,确定最佳提取工艺及检测条件。结果表明:建立以10 m L 80%丙酮为提取溶剂、以6 m L 200 g/L的KOH-甲醇溶液为皂化液,50℃皂化30 min为皂化条件的提取工艺;以C18(250 mm×4.6 mm,5μm)色谱柱,流动相为A.乙腈,B.乙酸乙酯,C.水,波长440nm,流速1 m L/min,柱温35℃为色谱检测条件的高效液相色谱检测方法。外标法进行定量,新黄质、紫黄质标准曲线线性关系良好,相关系数为0.998 9和0.998 7,方法平均回收率>70%,方法符合色谱检测要求,可用于辣椒叶片中新黄质、紫黄质含量检测。
