植物病原黄单胞菌菌黄素化学结构、生物学功能和生物合成机制研究进展

Research Progress of Xanthomonadin Chemical Structure, Biological Function and Biosynthesis Mechanism in Phytopathogen Xanthomonas

菌黄素是由植物病原黄单胞菌产生的一类附膜溴化芳香基多烯类黄色素,在溴取代、芳香环甲基化及多烯链链长方面存在结构多样性。菌黄素不仅作为黄单胞菌属的分类和诊断标记,还能保护细菌抵抗光氧化伤害,促进细菌在寄主植物表层的附生,在黄单胞菌致病性和环境适应性方面发挥重要作用。黄单胞菌基因组上一段pig基因簇负责菌黄素的生物合成,该基因簇介导了以3-羟基苯甲酸为前体物新型的II型聚酮合酶生物合成途径。本文将系统综述菌黄素结构、生物学功能和生物合成机制的研究进展。

Xanthomonadins are yellow, membrane-bound, brominated, aryl-polyene pigments produced by Xanthomonas bacteria. Xanthomonadins from different Xanthomonas spp. differ in bromination and methylation patterns and the polyene chain length. Xanthomonadin have become useful chemotaxonomic and diagnostic markers for Xanthomonas. Moreover, xanthomonadins play an important role in maintaining the ecological fitness of Xanthomonas species by protecting bacterial cells against photooxidative and peroxidative stress. A pig cluster has been isolated to be responsible for xanthomonadin biosynthesis. Function analysis of the pig cluster showed xanthomonadins are biosynthesized via an unusual type II polyketide synthase pathway, which utilize 3-hydroxybenzoic acid as precursor. This review discusses the chemical structure, biological function and biosynthesis mechanism of xanthomonadin.