奥雷乌西丁合成酶:一种多氧化酶同类物,负责花朵的颜色
T Nakayama1, K Yonekura-Sakakibara, T Sato
1Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aoba-yama 07, Sendai 980-8579, Japan. nakayama@seika.che.tohoku.ac.jp
Science (New York, N.Y.)
|November 10, 2000
概括
研究人员确定了黄氨酸合成酶,这种酶对于龙的黄色花的颜色至关重要. 这种含铜的葡萄糖蛋白催化了来自植物聚烯氧化酶家族的石英的光环合成.
科学领域:
- 植物生物化学 植物生物化学
- 分子生物学分子生物学
- 花色素的遗传学 花色素的遗传学
背景情况:
- 紫外线是黄色的黄类化合物,负责龙和宇宙等装饰植物的颜色.
- 植物中光合成的生物化学途径尚未完全阐明.
- 了解参与植物色素生产的酶是花特征研究的关键.
研究的目的:
- 为了识别和描述负责催化紫外线生物合成的酶,从黄色龙花中的 chalcones.
- 确定已识别的酶的分子身份和分类.
- 为了提供一个清晰的例子,在植物花的颜色的多氧化酶同类函数.
主要方法:
- 酶活性测定使用甲基前体.
- 蛋白质的净化和表征 (分子量,辅因子识别).
- 补充DNA (cDNA) 克隆和测序.
- 在花组织中的基因表达分析.
- 推断的蛋白质序列的生物信息分析.
主要成果:
- 一种叫做 aureusidin synthase 的酶被确定为负责光合成的酶.
- 奥雷乌西丁合成酶是一种39kDa含铜的葡萄糖蛋白.
- 该酶催化了特定的四基和五基前体的氧化和/或氧化循环.
- 编码 aureusidin synthase 的cDNA 在产生光的龙品种的花中得到表达.
- 序列分析将黄素合成酶置于植物多氧化酶家族中.
结论:
- 奥鲁西丁合成酶是龙光生物合成中的关键酶.
- 这项研究为多氧化酶同类在植物花朵色彩中的作用提供了明确的证据.
- 这些发现有助于理解花色素的遗传和生物化学基础.
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