Novel Curcumin Derivatives as Potent FtsZ-Targeting Bactericides against Rice Bacterial Leaf Blight

Area of Science:

• Agricultural Science
• Microbiology
• Medicinal Chemistry

Background:

• Rice bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae (Xoo), severely impacts global rice yields.
• Filamentous temperature-sensitive protein Z (FtsZ) is essential for bacterial cell division and a potential drug target.

Purpose of the Study:

• To design and evaluate curcumin derivatives targeting XooFtsZ for controlling BLB.
• To identify potent inhibitors of XooFtsZ with potential as novel bactericides.

Main Methods:

• Design and synthesis of 35 curcumin derivatives targeting XooFtsZ.
• In vitro anti-Xoo activity assessment (EC50 values) and greenhouse disease control trials.
• Analysis of B01's mechanism of action, including FtsZ binding, GTPase activity, and polymerization inhibition.

Main Results:

• Compound B01 demonstrated significant anti-Xoo activity (EC50 = 3.74 μg/mL), outperforming existing treatments.
• Greenhouse studies showed B01 achieved 73.2% BLB control efficacy with no phytotoxicity.
• B01 inhibits XooFtsZ by binding to specific residues, disrupting GTPase activity and FtsZ polymerization, leading to cell elongation.

Conclusions:

• Compound B01 is a highly effective XooFtsZ-targeted lead compound for developing novel bactericides against rice bacterial leaf blight.
• The findings support FtsZ as a viable target for combating Xoo infections in rice.