Wang Haoqi, Irigoyen Sonia, Liu Jiaxing, Ramasamy Manikandan, Padilla Carmen, Bedre Renesh, Yang Chuanyu, Thapa Shree P, Mulgaonkar Nirmitee, Ancona Veronica, He Ping, Coaker Gitta, Fernando Sandun, Mandadi Kranthi K
Biological and Agricultural Engineering Department, Texas A&M University, College Station, TX, USA.
Texas A&M AgriLife Research & Extension Center, Texas A&M University System, 2415 E. Highway 83, Weslaco TX 78596, USA.
iScience. 2024 Feb 15;27(3):109232. doi: 10.1016/j.isci.2024.109232. eCollection 2024 Mar 15.
"Candidatus Liberibacter spp." are insect-vectored, fastidious, and vascular-limited phytopathogens. They are the presumptive causal agents of potato zebra chip, tomato vein clearing, and the devastating citrus greening disease worldwide. There is an urgent need to develop new strategies to control them. In this study, we characterized a dual-specificity serine/tyrosine phosphatase (STP) that is well conserved among thirty-three geographically diverse " Liberibacter spp." and strains that infect multiple Solanaceaea and citrus spp. The STP is expressed in infected plant tissues, localized at the plant cytosol and plasma membrane, and interferes with plant cell death responses. We employed an target-based molecular modeling and ligand screen to identify two small molecules with high binding affinity to STP. Efficacy studies demonstrated that the two molecules can inhibit " Liberibacter spp." but not unrelated pathogens and confer plant disease tolerance. The inhibitors and strategies are promising means to control " Liberibacter spp."
“候选韧皮部杆菌属（Candidatus Liberibacter spp.）”是由昆虫传播、苛求且局限于维管束的植物病原体。它们被认为是全球范围内马铃薯斑马片病、番茄脉明病以及毁灭性柑橘黄龙病的致病因子。迫切需要开发新的策略来控制它们。在本研究中，我们鉴定了一种双特异性丝氨酸/酪氨酸磷酸酶（STP），该酶在来自不同地理区域的33种“韧皮部杆菌属”以及感染多种茄科植物和柑橘属植物的菌株中高度保守。STP在受感染的植物组织中表达，定位于植物细胞质和质膜，并干扰植物细胞死亡反应。我们采用基于靶点的分子建模和配体筛选来鉴定两种与STP具有高结合亲和力的小分子。功效研究表明，这两种分子可以抑制“韧皮部杆菌属”，但对无关病原体无抑制作用，并赋予植物病害耐受性。这些抑制剂和策略是控制“韧皮部杆菌属”的有前景的手段。
