【摘要】 运用病理组织学观察、病原菌分离鉴定、致病性测定及全基因组测序等技术解析1株高致病性维氏气单胞菌(Aeromonas veronii)的分子生物学特征。结果显示，自然感染加州鲈(Micropterus salmoides)表现出鳍条基部与肛门红肿、鳍条与皮肤溃烂等症状，分离获得1株优势菌，LB平板、鉴别培养基及革兰染色和gyrB测序结果证实该分离菌为维氏气单胞菌，命名为AY26;致病性试验结果显示，该菌株对加州鲈具有强致病性，回归感染后14 d内原菌液组病死率为100%,且病理特征与自然感染加州鲈相似；AY26全基因组测序结果显示，其基因组全长为4 505 265 bp, GC含量为60.13%;病原毒力因子数据库(VFDB)比对显示，分离菌携带多种与毒素、黏附、抗吞噬相关及分泌系统的毒力基因；耐药基因数据库(ARDB)分析显示，其携带26种耐药基因。结果表明，本试验从基因组层面揭示了AY26的毒力基因与耐药特征，为开发靶向毒力因子的防控策略及临床耐药性管理提供了理论依据。更多还原

【Abstract】 To address the bacterial diseases currently constraining the aquaculture of Micropterus salmoides, this study employed techniques including histopathological observation, pathogen isolation and identification, pathogenicity determination, and whole-genome sequencing to characterize the molecular and biological features of a highly pathogenic strain of Aeromonas veronii.Results showed that naturally infected Micropterus salmoides exhibited symptoms including redness and swelling at the base of fins and anus, along with ulceration of fins and skin.One dominant bacterial strain was isolated, and its identity as Aeromonas veronii(designated as AY26) was confirmed via LB agar culture, differential medium tests, Gram staining, and gyrB gene sequencing.Pathogenicity experiments demonstrated strong virulence of AY26 in Micropterus salmoides.The mortality rate reached 100% within 14 days in the group infected with the original bacterial suspension, with pathological characteristics consistent with those of naturally infected fish.Whole-genome sequencing of AY26 revealed a genome size of 4 505 265 bp and a GC content of 60.13%.Alignment against the Virulence Factor Database(VFDB) revealed that the isolate harbored multiple virulence genes associated with toxins, adhesion, anti-phagocytosis, and secretion systems.Analysis using the Antibiotic Resistance Genes Database(ARDB)identified 26 antibiotic resistance genes in AY26.This study elucidated the virulence genes and antibiotic resistance traits of AY26 at the genomic level,providing a theoretical basis for developing virulence factor-targeted control strategies and managing clinical antibiotic resistance.更多还原