Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory of Conservation and Utilization for Subtropical Agri-Biological Resources, Guangxi University, Nanning, Guangxi, China.
IRREC-IFAS, University, Fort Pierce, Florida, USA.
Mol Plant Pathol. 2024 Sep;25(9):e70001. doi: 10.1111/mpp.70001.
Xanthomonas albilineans (Xal) is a gram-negative bacterial pathogen responsible for developing sugarcane leaf scald disease, which engenders significant economic losses within the sugarcane industry. In the current study, homologous recombination exchange was carried out to induce mutations within the virB/D4-like type IV secretion system (T4SS) genes of Xal. The results revealed that the virB11-deletion mutant (ΔvirB11) exhibited a loss in swimming and twitching motility. Application of transmission electron microscopy analysis further demonstrated that the ΔvirB11 failed to develop flagella formation and type IV pilus morphology and exhibited reduced swarming behaviour and virulence. However, these alterations had no discernible impact on bacterial growth. Comparative transcriptome analysis between the wild-type Xal JG43 and the deletion-mutant ΔvirB11 revealed 123 differentially expressed genes (DEGs), of which 28 and 10 DEGs were notably associated with flagellar assembly and chemotaxis, respectively. In light of these findings, we postulate that virB11 plays an indispensable role in regulating the processes related to motility and chemotaxis in Xal.
黄单胞菌（Xal）是一种革兰氏阴性细菌病原体，可导致甘蔗叶枯病的发生，给甘蔗产业带来重大经济损失。在本研究中，采用同源重组交换的方法诱导 Xal 的 virB/D4 样 IV 型分泌系统（T4SS）基因发生突变。结果表明，virB11 缺失突变体（ΔvirB11）丧失了泳动和翻滚运动能力。透射电子显微镜分析进一步表明，ΔvirB11 无法形成鞭毛和 IV 型菌毛形态，其 swarm 行为和毒力降低。然而，这些变化对细菌生长没有明显影响。野生型 Xal JG43 和缺失突变体 ΔvirB11 之间的比较转录组分析显示，有 123 个差异表达基因（DEGs），其中 28 个和 10 个 DEGs 分别与鞭毛组装和趋化性显著相关。根据这些发现，我们推测 virB11 在调节 Xal 运动和趋化性相关过程中起着不可或缺的作用。
