广东农业科学2025，Vol.52Issue(2)：82-94,13.DOI:10.16768/j.issn.1004-874X.2025.02.007
黄颡鱼源致病性嗜水气单胞菌A01的分离鉴定、全基因组特征及比较基因分析
Isolation,Identification,Whole-genome Characterization,and Comparative Genomic Analysis of Pathogenic Aeromonas hydrophila A01 from Pelteobagrus fulvidraco
摘要
Abstract
[Objective]This study aims to investigate the genomic characteristics,virulence,and drug resistance of a pathogenic Aeromonas hydrophila strain isolated from the liver of a diseased Pelteobagrus fulvidraco from a large aquaculture farm in Shanghai.This analysis seeks to provide theoretical insights into the etiology,prevention,and control of the disease.[Method]Bacterial strains were isolated and purified bacterial strains from the affected fish,and their identification was based on morphological,physiological,and biochemical traits.PCR detection for virulence genes and drug sensitivity tests were conducted.Strain A01 underwent whole-genome sequencing using the Illumina platform,followed by genome assembly with SPAdes,gene prediction via Prokka,and functional annotation through KEGG,GO,and COG databases.The VFDB and CARD/AMRFinderPlus databases facilitated the identification of virulence and resistance genes,respectively.Strain affinities were evaluated through ANI analysis and phylogenetic tree construction based on homologous single-copy genes,complemented by multilocus sequence typing(MLST)to discern genetic backgrounds.[Result]The pathogenic bacterium A01 of P.fulvidraco is A.hydrophila,with a circular genome of approximately 4.93 Mb in length and a GC content of 61.09%.It encodes 4 500 protein genes,121 tRNAs,and 3 rRNAs.Functional annotation highlighted its genes were involved in carbohydrate metabolism,amino acid metabolism,and membrane transport,suggesting strong environmental adaptability.Analysis uncovered 527 virulence-related genes,encompassing flagellar assembly,chemotaxis,and secretion system genes,pointing to A01's high invasiveness and pathogenicity.Additionally,279 resistance genes were identified,including antibiotics such as β-lactams,tetracyclines,aminoglycosides,and polymyxins,indicating a significantly higher MDR risk compared to the reference strain ATCC7966.ANI analysis(>96%)and phylogenetic trees confirmed A01 was closely related to ATCC7966,while MLST typing hinted at a possible correlation between genetic differentiation and variations in pathogenicity and drug resistance.A01 carries nine important virulence genes(aer,act,fla,lip,gcaT,exu,ast,alt and ahyB),indicating strong pathogenicity.Drug sensitivity tests showed that A01 exhibits multidrug resistance(MDR)to 16 of the 24 antibiotics tested.[Conclusion]This whole-genome analysis of A.hydrophila strain A01 from P.fulvidraco revealed fundamental genomic characteristics,virulence levels,and resistance gene levels,laying a theoretical groundwork for future studies on the infection mechanism of this pathogen in P.fulvidraco.关键词
黄颡鱼/嗜水气单胞菌/全基因组测序/毒力基因/耐药基因/比较基因组学Key words
Pelteobagrus fulvidraco/Aeromonas hydrophila/whole-genome sequencing/virulence genes/antimicrobial resistance genes/comparative genomics分类
农业科技引用本文复制引用
高玮,邵玲..黄颡鱼源致病性嗜水气单胞菌A01的分离鉴定、全基因组特征及比较基因分析[J].广东农业科学,2025,52(2):82-94,13.基金项目
上海市农业科技创新项目(沪农科[T2024205]) （沪农科[T2024205]）
上海市青年科技启明星计划(21QA1408300) （21QA1408300）
上海市自然科学基金(21ZR1457800) （21ZR1457800）
