Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China.
Key Laboratory of Surveillance and Management for Plant Quarantine Pests, Ministry of Agriculture and Rural Affairs, Beijing Key Laboratory of Seed Disease Testing and Control, China Agricultural University, Beijing 100193, China.
Int J Mol Sci. 2023 Mar 10;24(6):5324. doi: 10.3390/ijms24065324.
Penicillin-binding proteins (PBPs) are considered essential for bacterial peptidoglycan biosynthesis and cell wall assembly. is a representative Gram-positive bacterial species that causes bacterial canker in tomato. plays a significant role in maintaining cell morphological characteristics and stress responses in . The current study demonstrated that the deletion of commonly enhances bacterial pathogenicity in and revealed the mechanisms through which this occurs. The expression of interrelated virulence genes, including , and , were significantly upregulated in △ mutants. Compared with those in wild-type strains, exoenzyme activities, the formation of biofilm, and the production of exopolysaccharides (EPS) were significantly increased in △ mutants. It is noteworthy that EPS were responsible for the enhancement in bacterial pathogenicity, with the degree of necrotic tomato stem cankers intensifying with the injection of a gradient of EPS from . These findings highlight new insights into the role of affecting bacterial pathogenicity, with an emphasis on EPS, advancing the current understanding of phytopathogenic infection strategies for Gram-positive bacteria.
青霉素结合蛋白（PBPs）被认为是细菌肽聚糖生物合成和细胞壁组装所必需的。 是一种代表革兰氏阳性细菌物种，可导致番茄细菌性溃疡。 在 中， 对于维持细胞形态特征和应激反应具有重要作用。本研究表明， 缺失通常会增强 在 中的致病性，并揭示了发生这种情况的机制。相关毒力基因，包括 、 和 ，在 △突变体中的表达显著上调。与野生型菌株相比， △突变体中外切酶活性、生物膜形成和胞外多糖（EPS）的产生显著增加。值得注意的是，EPS 负责增强细菌的致病性，随着从 中注射 EPS 梯度的增加，番茄茎溃疡的坏死程度加剧。这些发现为 影响细菌致病性的作用提供了新的见解，重点是 EPS，提高了对革兰氏阳性细菌植物病原感染策略的现有理解。
