Innovative Strategy for the Control of Citrus Canker: Inhibitors Targeting the Type III Secretion System of Xanthomonas citri Subsp. citri

Abstract

To find potential type III secretion system (T3SS) inhibitors against citrus canker caused by Xanthomonas citri subsp. citri (Xcc), a new series of 5-phenyl-2-furan carboxylic acid derivatives stitched with 2-mercapto-1,3,4-thiadiazole were designed and synthesized. Among the 30 compounds synthesized, 14 compounds significantly inhibited the promoter activity of a harpin gene hpa1. Eight of the 14 compounds did not affect the growth of Xcc, but significantly reduced the hypersensitive response (HR) of tobacco and decreased the pathogenicity of Xcc on citrus plants. Subsequent studies have demonstrated that these inhibitory molecules effectively suppress the T3SS of Xcc and significantly impair the pathogen’s ability to subvert citrus immunity, resulting in a reduction in the level of disease progression. As a result, our work has identified a series of potentially attractive agents for the control of citrus canker.

Combined metabolome and transcriptome reveal HmF6’H1 regulating simple coumarin accumulation against powdery mildew infection in Heracleum moellendorffii Hance

“…Plant metabolites can be classified into primary and secondary metabolites. Secondary metabolites play a crucial role in plant-pathogen interactions by directly inhibiting pathogen invasion or establishing physical barriers to prevent infection [ 29 – 31 ]. Combining transcriptome and metabolomic analysis offers an effective method for finding crucial metabolites and genes that respond to pathogen infections [ 32 – 34 ].…”

Antibacterial Mechanism, Control Efficiency, and Nontarget Toxicity Evaluation of Actinomycin X2 against Xanthomonas citri Subsp. citri

“…Previous studies have identified some anti-Xcc compounds, such as triclosan derivatives, N -acetylcysteine, and 2-(butyldisulfanyl)­quinazoline-4­(3 H )-one, all of which significantly inhibit the biofilm formation of Xcc. − Furthermore, the development of inhibitors targeting the type III secretion system, which is essential for Xcc to exert virulence, represents a novel strategy. It is reported that 5-phenyl-2-furan carboxylic acid is capable of disrupting the type III secretion system of Xcc, making this bacteria fail to produce citrus canker symptoms such as forming lesions even if it enters into and infects the citrus tissues …”

Visible‐light‐driven water‐soluble zinc oxide quantum dots for efficient control of citrus canker

“…citri (Xcc) is a devastating bacterial disease that reduces citrus yield and quality, posing a serious threat to the citrus industry 2 . Several management strategies have been developed to reduce citrus canker, including the breeding of resistant varieties and the use of biological, chemical and copper‐based control agents 3–6 . However, developing resistant varieties and biological control approaches takes time.…”