Laboratory of Pathology and Immunology of Aquatic Animals, School of Marine Life and Fisheries, Jiangsu Ocean University, Lianyungang, 222005, China.
Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang, 222005, China.
Vet Res Commun. 2024 Nov 15;49(1):7. doi: 10.1007/s11259-024-10594-8.
Aeromonas veronii has emerged as a significant pathogen that impacts both fish and mammals. Recently, an infectious disease characterized by multiple ulcers on the body surface with a high mortality rate occurred in Channa argus cultured in Jiangsu Province, China. A Gram-negative bacterial strain (Aer12) was isolated from the body surface of the diseased fish and identified as A. veronii by the physiological, biochemical, and 16 S rRNA gene analysis. Intra-peritoneal injection of Aer12 into the healthy C. argus resulted in the development of multiple ulcers on the body surface, and the histopathological results showed that muscle tissue rupture was the most severe symptom. Aer12 showed both protease and lipase activities with no β-hemolytic activity. Furthermore, Aer12 contained seven virulence genes (aer, act, alt, fla, ascV, aexT, and ela) and one antibiotic resistance gene (qnrS) identified by the PCR assay. The results of whole genome sequencing revealed that Aer12 had a circular chromosome that measured 4,719,428 bp. It comprised 4301 predicted protein-coding sequences (CDS) in addition to 31 rRNA, 124 tRNA, and 49 sRNA genes. Furthermore, a total of 676 virulence genes and 216 antibiotic resistance genes have been predicted. Aer12 was susceptible to 21 antibiotics, including ampicillin and erythromycin. The results of Chinese herbs susceptibility assay showed that Aer12 was highly susceptible to Sanguisorba officinalis, Galla chinensis, and Schisandra chinensis. The results of this study will serve as a reference for future research on the pathogenic mechanism of A. veronii and the prevention and control of bacterial diseases in C. argus farming.
维氏气单胞菌已成为影响鱼类和哺乳动物的重要病原体。最近，在中国江苏省养殖的乌鳢出现了一种以体表多发性溃疡和高死亡率为特征的传染病。从患病乌鳢体表分离到一株革兰氏阴性细菌（Aer12），通过生理生化和 16S rRNA 基因分析鉴定为维氏气单胞菌。将 Aer12 腹腔注射到健康的乌鳢体内，导致其体表出现多发性溃疡，组织病理学结果表明肌肉组织破裂是最严重的症状。Aer12 具有蛋白酶和脂肪酶活性，但无β-溶血活性。此外，通过 PCR 检测发现 Aer12 含有 7 个毒力基因（aer、act、alt、fla、ascV、aexT 和 ela）和 1 个抗生素耐药基因（qnrS）。全基因组测序结果表明，Aer12 有一个 4,719,428 bp 的环状染色体，包含 4301 个预测蛋白编码序列（CDS），此外还有 31 个 rRNA、124 个 tRNA 和 49 个 sRNA 基因。此外，共预测到 676 个毒力基因和 216 个抗生素耐药基因。Aer12 对 21 种抗生素敏感，包括氨苄西林和红霉素。中草药药敏试验结果表明，Aer12 对苦地丁、五倍子和五味子高度敏感。本研究结果将为进一步研究维氏气单胞菌的致病机制以及乌鳢细菌性疾病的防控提供参考。
