Exploring Aeromonas dhakensis in Aldabra giant tortoises: a debut report and genetic characterization

作者：Chenxu Zhao, Panpan Qin, Shuai Li, Zilu Chen, Tianliang Wang, Qunchao Liang, W Y He, Zeyu Peng, Zeyu Peng, Yurong Yang, Zhifeng Peng, Zhifeng Peng, Yongtao Li · 发表于：BMC Microbiology · 年份：2024 · DOI：10.1186/s12866-024-03203-w · 被引用次数：5 · 研究领域：Aquaculture disease management and microbiota、Turtle Biology and Conservation、Rabies epidemiology and control

Abstract Aeromonas dhakensis (A. dhakensis) is becoming an emerging pathogen worldwide, with an increasingly significant role in animals and human health. It is a ubiquitous bacteria found in terrestrial and aquatic milieus. However, there have been few reports of reptile infections. In this study, a bacterial strain isolated from a dead Aldabra giant tortoise was identified as A. dhakensis HN-1 through clinical observation, matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF/MS), and gene sequencing analysis. Subsequently, to evaluate its pathogenicity, the detection of virulence genes and mice infection experiments were performed. A. dhakensis HN-1 was found to contain seven virulence genes, including alt , ela , lip , act , aerA , fla , and hlyA . Mice infected with A. dhakensis HN-1 exhibited hemorrhage of varying degrees in multiple organs. The half-maximal lethal dose (LD 50 ) value of A. dhakensis HN-1 for mice was estimated to be 2.05 × 10 7 colony forming units (CFU)/mL. The antimicrobial susceptibility test revealed that A. dhakensis HN-1 was resistant to amoxicillin, penicillin, ampicillin and erythromycin. This is the first report of A. dhakensis in Aldabra giant tortoises, expanding the currently known host spectrum. Our findings emphasize the need for One Health surveillance and extensive research to reduce the spread of A. dhakensis across the environment, humans, and animals.