ICAR-NBAIM, Kushmaur, Maunath Bhanjan (UP)-275103, India,
Regional Medical research Center, Bhubaneswar-751023, India.
Front Biosci (Landmark Ed). 2020 Jan 1;25(2):335-362. doi: 10.2741/4809.
PolyGalacturonase Inhibiting Proteins (PGIPs) are leucine rich repeat pathogenesis-related (PR) cell wall proteins, which interact and inhibit the PolyGalacturonase (PG), an enzyme secreted by the pathogen to degrade pectin. Interaction of PGIP with PG limits the vulnerability of PG by the activation of host defense response against pathogenic attack. is gram-negative soft rot bacteria responsible for rhizome rot disease in banana and many other crop plants. The interaction of PG with PGIP is one of the crucial steps for plant-pathogen interaction. To study the molecular mechanism of PR proteins, we employed molecular modelling, protein-protein docking and molecular dynamics simulations of banana PGIP (bPGIP) with PG (ecPG). Further, insilico site-directed mutagenesis was performed in PGIP (pvPGIP2) to elucidate the interaction with ecPG. Docking and simulation studies divulge that binding of bPGIP and PvPGIP2 with active site residues of EcPG induces structural changes and thereby inhibit the enzyme. This study provides a unique insight into PG-PGIP interaction, which may help in the development of bacterial soft-rot resistant banana cultivars.
多聚半乳糖醛酸酶抑制蛋白（PGIPs）是富含亮氨酸的重复病程相关（PR）细胞壁蛋白，与多聚半乳糖醛酸酶（PG）相互作用并抑制其活性。PG 是由病原体分泌的一种酶，可降解果胶。PGIP 与 PG 的相互作用通过激活宿主防御反应来限制 PG 的易感性，从而抵御病原体的攻击。是一种革兰氏阴性软腐细菌，可导致香蕉和许多其他作物的根茎腐烂病。PG 与 PGIP 的相互作用是植物-病原体相互作用的关键步骤之一。为了研究 PR 蛋白的分子机制，我们采用了分子建模、蛋白-蛋白对接和香蕉 PGIP（bPGIP）与 PG（ecPG）的分子动力学模拟。此外，还对 PGIP（pvPGIP2）进行了计算机定点突变，以阐明与 ecPG 的相互作用。对接和模拟研究表明，bPGIP 和 PvPGIP2 与 EcPG 的活性位点残基结合会诱导结构变化，从而抑制酶的活性。这项研究为 PG-PGIP 相互作用提供了独特的见解，这可能有助于开发具有细菌性软腐病抗性的香蕉品种。
