1Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil.
2Department of Plant Sciences, University of California, Davis, CA 95616, U.S.A.
Phytopathology. 2019 Aug;109(8):1344-1353. doi: 10.1094/PHYTO-03-19-0083-R. Epub 2019 Jul 5.
releases outer membrane vesicles (OMVs) known to play a role in the systemic dissemination of this pathogen. OMVs inhibit bacterial attachment to xylem wall and traffic lipases/esterases that act on the degradation of plant cell wall. Here, we extended the characterization of OMVs by identifying proteins and metabolites potentially associated with OMVs produced by Temecula1, a Pierce's disease strain, and by 9a5c and Fb7, two citrus variegated chlorosis strains. These results strengthen that one of the OMVs multiple functions is to carry determinants of virulence, such as lipases/esterases, adhesins, proteases, porins, and a pectin lyase-like protein. For the first time, we show that the two citrus variegated chlorosis strains produce diffusible signaling factor 2 (DSF2) and citrus variegated chlorosis-DSF (likewise, Temecula1) and most importantly, that these compounds of the DSF ( DSF) family are associated with OMV-enriched fractions. Altogether, our findings widen the potential functions of OMVs in intercellular signaling and host-pathogen interactions.
释放已知在外膜囊泡（OMVs）中发挥作用的全身性传播这种病原体。OMVs 抑制细菌附着在木质部壁和交通脂肪酶/酯酶，对植物细胞壁的降解作用。在这里，我们通过鉴定蛋白质和代谢物，扩展了 Temecula1（一种皮尔氏病菌株）和 9a5c 和 Fb7（两种柑橘斑驳黄化菌株）产生的 OMVs 的特征，这些代谢物可能与 OMVs 有关。这些结果进一步证实，OMVs 的多种功能之一是携带毒力决定因素，如脂肪酶/酯酶、黏附素、蛋白酶、孔蛋白和果胶裂解酶样蛋白。这是首次表明，这两个柑橘斑驳黄化菌株产生扩散信号因子 2（DSF2）和柑橘斑驳黄化-DSF（同样，Temecula1），最重要的是，这些 DSF（DSF）家族的化合物与富含 OMV 的部分有关。总的来说，我们的研究结果拓宽了 OMVs 在细胞间信号传递和宿主-病原体相互作用中的潜在功能。
