Antifungal Compound from the Predatory Bacterium <i>Lysobacter enzymogenes</i> Inhibits a Plant Pathogenic Fungus by Targeting the AAA ATPase VpVeb1
Rongxian Hou, Kaihuai Li, Baodian Guo, Yangyang Zhao, Chaohui Li, Bao Quoc Tang, Weibo Sun, Bo Wang, Wenchan Chen, Cong Sheng, Jialiang Kan, Yancun Zhao, Fengquan Liu
Abstract
Heat-stable antifungal factor (HSAF) isolated from Lysobacter enzymogenes is considered a potential biocontrol agent. However, the target of HSAF in phytopathogenic fungi remains unclear. In this study, we investigated the target of HSAF in Valsa pyri that causes fatal pear Valsa canker. Thirty-one HSAF-binding proteins were captured and identified by surface plasmon resonance (SPR) and high-performance liquid chromatography–mass spectrometry (LC–MS/MS), and 11 deletion mutants were obtained. Among these mutants, only Δ VpVEB1 showed decreased sensitivity to HSAF. Additionally, Δ VpVEB1 exhibited significantly reduced virulence in V. pyri . Molecular docking and SPR results revealed that HSAF bound to threonine 569 and glycine 570 of VpVeb1, which are crucial for AAA ATPase activity. Another study showed that HSAF could decrease the ATPase activity of VpVeb1, leading to the reduced virulence of V. pyri . Taken together, this study first identified the potential target of HSAF in fungi. These findings will help us better understand the model of action of HSAF to fungi.