一株高致病性棘胸蛙源嗜水气单胞菌的全基因组测序及其感染后脾的超微病理损伤  

Complete Genome Sequence of a Highly Pathogenic Aeromonas hydrophila Isolated from Quasipaa Spinose and Resultant Ultrastructural Pathology of Spleen

作　　者：任思宇[1] 吴春艳[1] 刘震坤[1] 杨延辉 李新善 REN Siyu;WU Chunyan;LIU Zhenkun;YANG Yanhui;LI Xinshan(Chongqing Three Gorges Vocational College,Wanzhou 404155,Chongqing,China)

机构地区：[1]重庆三峡职业学院,重庆万州404155

出　　处：《四川农业大学学报》2025年第1期48-56,共9页Journal of Sichuan Agricultural University

基　　金：重庆市万州区科技局博士直通车项目(wzstc2022010);重庆市教委科研项目(KJQN202203514);重庆三峡职业学院创新团队(sxzy-2023td-006)。

摘　　要：【目的】了解棘胸蛙源嗜水气单胞菌SZW-003菌株的全基因组学特征,明确感染后棘胸蛙脾脏的超微病理损伤,为嗜水气单胞菌的病原学研究及病害防控提供基础资料。【方法】提取SZW-003菌株全基因组DNA构建文库后测序,组装后进行注释分析,结合动态超微病理观察感染后棘胸蛙脾脏的损伤。【结果】SZW-003菌株具备β溶血特性,全基因组总长度为4925442 bp,GC含量为60.64%,编码基因数量为4473个,预测有388个毒力基因。感染后棘胸蛙脾内网状细胞最早发生损伤,也是最早发现吞噬有病原菌的细胞类型;在感染胁迫下,网状细胞大量脱落转化为巨噬细胞和黑色素巨噬细胞;随着病程发展,网状细胞肿胀裂解,脾窦内皮细胞大量坏死,细胞碎片与异形红细胞分布其中,残存的巨噬细胞内可见病原菌。【结论】SZW-003菌株是一株强毒力的嗜水气单胞菌,感染后可导致脾组织结构裂解,细胞成分坏死,引起网状细胞向巨噬细胞与黑色素巨噬细胞转化,造成严重的损伤。【Objective】This study aims to explore the whole genome sequencing of a highly pathogenic Aeromonas hydrophila SZW-003 strain isolated from Quasipaa spinose,and to clarify the ultrastructural pathology after spleen infection,so as to provide a theoretical basis for etiological research and prevention and control of diseases caused by A.hydrophila.【Method】Genomic DNA was extracted from SZW-003 strain,the sequence was assembled,and the genome was annotated while observing the resultant dynamic ultrastructural pathology of spleen injury.【Result】Strain SZW-003 possessedβ-hemolysis characteristics.The results showed that SZW-003 contained a chromosome of 4925442 bp with an average G+C content of 60.64%and 4473 coding genes,and 388 virulence factors were predicted in the VFDB database.The reticular cells in spleen of Quasipaa spinose were the first to be damaged with phagocytic pathogens inside after infection,and it was also the first cell type that swallowed pathogenic bacteria.Meanwhile,a large number of reticular cells were shed and transformed into macrophages and melanin macrophages.As the disease deteriorates,the reticular cells were swollen and lysed,the endothelial cells in the blood sinuses were necrotic in a large area,and a large number of scattered cell fragments and anomalous red blood cells could be seen in the splenic sinuses,and bacteria could be observed in the remaining macrophages【Conclusion】SZW-003 strain was a highly pathogenic Aeromonas hy⁃drophila.After invasion and infection,it caused splenic tissue structure disruption,with splenic reticular cells transforming into macrophages and melanin macrophages,causing severe damage.

关 键 词：棘胸蛙 嗜水气单胞菌 全基因组 超微病理损伤 

分 类 号：S948[农业科学—水产养殖]