Involvement of hrpX and hrpG in the Virulence of Acidovorax citrulli Strain Aac5, Causal Agent of Bacterial Fruit Blotch in Cucurbits.

摘要: Acidovorax citrulli causes bacterial fruit blotch, a disease that poses global threat to watermelon and melon production. Despite its economic importance, relatively little is known about the molecular mechanisms of pathogenicity virulence A. citrulli. Like other plant-pathogenic bacteria, relies on type III secretion system (T3SS) for pathogenicity. On basis sequence operon arrangement analyses, was found have class II hrp gene cluster similar those Xanthomonas Ralstonia spp. In cluster, hrpG hrpX play key roles in regulation T3SS effectors. However, This study aimed investigate We or deletion mutants group strain Aac5 had reduced seedlings, failed induce hypersensitive response tobacco, elicited higher levels reactive oxygen species Nicotiana benthamiana than wild-type strain. Additionally, we demonstrated HrpG activates HrpX Moreover, transcription translation 3-secreted effector (T3E) Aac5_2166 were suppressed mutants. Notably, appeared modulate biofilm formation. These results suggest are essential pathogenicity, T3Es, formation