Misas-Villamil Johana C, van der Hoorn Renier A L
Plant Chemetics Laboratory, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, 50829 Cologne, Germany.
Curr Opin Plant Biol. 2008 Aug;11(4):380-8. doi: 10.1016/j.pbi.2008.04.007. Epub 2008 Jun 10.
The plant apoplast during plant-pathogen interactions is an ancient battleground that holds an intriguing range of attacking enzymes and counteracting inhibitors. Examples are pathogen xylanases and polygalacturonases that are inhibited by plant proteins like TAXI, XIP, and PGIP; and plant glucanases and proteases, which are targeted by pathogen proteins such as GIP1, EPI1, EPIC2B, and AVR2. These seven well-characterized inhibitors have different modes of action and many probably evolved from inactive enzymes themselves. Detailed studies of the structures, sequence variation, and mutated proteins uncovered molecular struggles between these enzymes and their inhibitors, resulting in positive selection for variant residues at the contact surface, where single residues determine the outcome of the interaction.
在植物与病原体相互作用过程中，植物质外体是一个古老的战场，其中存在一系列有趣的攻击酶和起对抗作用的抑制剂。例如，病原体木聚糖酶和多聚半乳糖醛酸酶会受到植物蛋白（如TAXI、XIP和PGIP）的抑制；而植物葡聚糖酶和蛋白酶则是病原体蛋白（如GIP1、EPI1、EPIC2B和AVR2）的作用靶点。这七种特征明确的抑制剂具有不同的作用模式，其中许多可能本身就是从无活性的酶进化而来的。对这些酶及其抑制剂的结构、序列变异和突变蛋白的详细研究揭示了它们之间的分子较量，导致在接触表面的变异残基受到正选择，单个残基决定了相互作用的结果。
