Characterization and Inhibition of Plant and Bacterial Protoporphyrinogen Oxidase

原卟啉原氧化酶是植物系统中血红素和叶绿素合成中的一种酶。最初的实验集中在二苯醚除草剂的机制，最近发现的抑制剂，通过植物细胞器提取物和纯化酶影响原卟啉原氧化。这些除草剂对原卟啉原氧化的抑制作用正在对大麦（对二苯醚敏感）和大豆（似乎具有抗性）的叶绿体和线粒体进行研究。100多年前，血液中的红色色素和树叶中的绿色色素在结构上相互关联。它们都含有一种叫做卟啉的有机成分。虽然我们对动物合成途径的了解相当广泛，但我们对植物（和细菌）如何制造卟啉的了解仍然相当有限。本项目重点研究植物途径中一个非常重要但又比较困难的酶。研究抑制叶绿素形成的除草剂已成为一种新的工具。这有望在植物生物学这个有些棘手的领域取得新的进展。

Protoporphyrinogen oxidase, an enzyme in heme and chlorophyll synthesis, is being characterized in plant systems. The initial experiments focus on the mechanism by which diphenyl ether herbicides, recently identified as inhibitors of this enzyme, affect protoporphyrinogen oxidation by extracts of plant organelles and by the purified enzyme. Inhibition of protoporphyrinogen oxidation by these herbicides is being examined in chloroplasts and mitochondria from barley, which is sensitive to diphenyl ethers, and soybean, which appears to be resistant. The red pigment of blood and the green pigment of leaves were shown to be related to each other structurally more than 100 years ago. They both contain organic portions called porphyrins. Although our knowledge of the synthetic pathways in animals is quite extensive, our knowledge of how plants (and bacteria) make porphyrins is still quite limited. This project focuses on a very important but difficult to study enzyme of the plant pathway. A new tool has become available for the study in a herbicide which inhibits the formation ofchlorophyll. This promises new advances in a somewhat intractable area of plant biology.