Chemical Biology Research Group, RIKEN CSRS, Wako, Saitama, Japan.
Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
Biosci Biotechnol Biochem. 2021 Jan 7;85(1):126-133. doi: 10.1093/bbb/zbaa035.
Pyricularia oryzae is one of the most devastating plant pathogens in the world. This fungus produces several secondary metabolites including the phytotoxin pyriculols, which are classified into 2 types: aldehyde form (pyriculol and pyriculariol) and alcohol form (dihydropyriculol and dihydropyriculariol). Although interconversion between the aldehyde form and alcohol form has been predicted, and the PYC10 gene for the oxidation of alcohol form to aldehyde is known, the gene responsible for the reduction of aldehyde to alcohol form is unknown. Furthermore, previous studies have predicted that alcohol analogs are biosynthesized via aldehyde analogs. Herein, we demonstrated that an aldo/keto reductase PYC7 is responsible for the reduction of aldehyde to alcohol congeners. The results indicate that aldehyde analogs are biosynthesized via alcohol analogs, contradicting the previous prediction. The results suggest that P. oryzae controls the amount of pyriculol analogs using two oxidoreductases, PYC7 and PYC10, thereby controlling the bioactivity of the phytotoxin.
稻梨孢菌是世界上最具破坏性的植物病原体之一。这种真菌产生多种次生代谢物，包括植物毒素稻瘟灵，它分为 2 种类型：醛形式（稻瘟灵和稻瘟灵醇）和醇形式（二氢稻瘟灵和二氢稻瘟灵醇）。尽管醛形式和醇形式之间的互变已经被预测到，并且已知 PYC10 基因负责将醇形式氧化为醛形式，但负责将醛形式还原为醇形式的基因尚不清楚。此外，先前的研究预测醇类似物是通过醛类似物生物合成的。本文证明了醛/酮还原酶 PYC7 负责将醛还原为醇同系物。结果表明，醛类似物是通过醇类似物生物合成的，这与之前的预测相矛盾。研究结果表明，稻梨孢菌使用两种氧化还原酶 PYC7 和 PYC10 来控制稻瘟灵类似物的数量，从而控制植物毒素的生物活性。
