Wang Zhihao, Lv Xiaolong, Kong Lanfang, Nawaz Saqib, Che Chuanyan, Chen Zhaoguo, Yin Huifang, Huang Cuiqin, Bao Yinli, Jiang Wei, Han Xiangan
Shanghai Veterinary Research Institute, The Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China.
College of Animal Science, Anhui Science and Technology University, Fengyang, 233100, China.
Adv Biol (Weinh). 2025 Jul 9:e00190. doi: 10.1002/adbi.202500190.
Bis-(3'-5')-cyclic diguanylic acid (c-di-GMP), a ubiquitous secondary messenger, affects multiple biological characteristics, including biofilm formation in avian pathogenic Escherichia coli (APEC). C-di-GMP is synthesized by diguanylate cyclase harboring a GGDEF domain and degraded by phosphodiesterase harboring either an EAL or an HD-GYP domain. However, the roles of PdeN, encoding a CSS-EAL domain, are uncharacterized. In this study, it is demonstrated that lacking pdeN significantly promotes biofilm formation and reduces the motility of the clinically isolated APEC O2 serotype strain DE17. In addition, macrocolony morphotypes showed that the ΔpdeN strain exhibits increasing production of curli fibers and cellulose, which is consistent with the results of RNA-seq and qPCR. Further exploration shows that lactose permease LacY and mannose permease subunit ManZ interact with PdeN. Infection experiments show that lacking pdeN significantly reduced the release of LDH in HD-11 cells and adhesion capacity to DF-1 cells. In conclusion, c-di-GMP metabolic gene pdeN involves biofilm formation and pathogenicity of APEC. Besides, it interacts with LacY and ManZ. Those results provide a basis for the prevention and control of APEC from the perspective of biofilm and carbohydrate metabolism.
双（3'-5'）-环二鸟苷酸（c-di-GMP）是一种普遍存在的第二信使，影响多种生物学特性，包括禽致病性大肠杆菌（APEC）中的生物膜形成。c-di-GMP由具有GGDEF结构域的二鸟苷酸环化酶合成，并由具有EAL或HD-GYP结构域的磷酸二酯酶降解。然而，编码CSS-EAL结构域的PdeN的作用尚未明确。在本研究中，证明缺失pdeN显著促进生物膜形成并降低临床分离的APEC O2血清型菌株DE17的运动性。此外，大菌落形态型显示ΔpdeN菌株的卷曲纤维和纤维素产量增加，这与RNA测序和qPCR结果一致。进一步探索表明，乳糖通透酶LacY和甘露糖通透酶亚基ManZ与PdeN相互作用。感染实验表明，缺失pdeN显著降低HD-11细胞中乳酸脱氢酶的释放以及对DF-1细胞的粘附能力。总之，c-di-GMP代谢基因pdeN参与APEC的生物膜形成和致病性。此外，它与LacY和ManZ相互作用。这些结果为从生物膜和碳水化合物代谢的角度预防和控制APEC提供了依据。
