Plant Pathology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
Mol Plant Pathol. 2003 Sep 1;4(5):421-5. doi: 10.1046/j.1364-3703.2003.00179.x.
SUMMARY Lipopolysaccharides (LPS) are ubiquitous, indispensable components of the cell surface of Gram-negative bacteria that apparently have diverse roles in bacterial pathogenesis of plants. As an outer membrane component, LPS may contribute to the exclusion of plant-derived antimicrobial compounds promoting the ability of a bacterial plant pathogen to infect plants. In contrast, LPS can be recognized by plants to directly trigger some plant defence-related responses. LPS also sensitize plant tissue to respond more rapidly or to a greater extent to subsequently inoculated phytopathogenic bacteria. Sensitization is manifested by an accelerated synthesis of antimicrobial hydroxycinnamoyl-tyramine conjugates, in the expression patterns of genes coding for some pathogenesis-related (PR) proteins, and prevention of the hypersensitive reaction caused by avirulent bacteria. The description at the molecular level of the various effects of LPS on plants is a necessary step towards an understanding of the signal transduction mechanisms through which LPS triggers these responses. A definition of these signal transduction pathways should allow an assessment of the contribution that LPS signalling makes to plant disease resistance in both natural infections and biocontrol.
摘要 脂多糖（LPS）是革兰氏阴性细菌细胞表面普遍存在的、不可或缺的组成部分，在植物病原菌的致病过程中显然具有多种作用。作为外膜的组成部分，LPS 可能有助于阻止植物来源的抗菌化合物的排出，从而促进细菌植物病原体感染植物的能力。相反，LPS 可以被植物识别，直接引发一些与植物防御相关的反应。LPS 还使植物组织对随后接种的植物病原菌更快或更大程度地产生反应。致敏表现为加速合成抗菌羟基肉桂酰基-酪胺缀合物，表现在编码某些病程相关（PR）蛋白的基因表达模式上，并防止无毒细菌引起的过敏反应。在分子水平上描述 LPS 对植物的各种影响是理解 LPS 触发这些反应的信号转导机制的必要步骤。这些信号转导途径的定义应能评估 LPS 信号在自然感染和生物防治中对植物抗病性的贡献。
