Complete genome sequence and comparative genomics of the golden pompano ( Trachinotus ovatus ) pathogen, V ibrio harveyi strain QT520

PeerJ

article

Zhigang Tu¹  Hongyue Li⁴  Xiang Zhang¹  Yun Sun¹  Yongcan Zhou¹ 

[1] State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University;Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University;Hainan Academy of Ocean and Fisheries Sciences;Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, College of Marine Science, Hainan University

关键词: Vibrio harveyi;    Antibiotic resistance;    Genome;    Virulence factor;    Plasmid;   

DOI  :  10.7717/peerj.4127

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Vibrio harveyi is a Gram-negative, halophilic bacterium that is an opportunistic pathogen of commercially farmed marine vertebrate species. To understand the pathogenicity of this species, the genome of V. harveyi QT520 was analyzed and compared to that of other strains. The results showed the genome of QT520 has two unique circular chromosomes and three endogenous plasmids, totaling 6,070,846 bp with a 45% GC content, 5,701 predicted ORFs, 134 tRNAs and 37 rRNAs. Common virulence factors, including ACF, IlpA, OmpU, Flagellin, Cya, Hemolysin and MARTX, were detected in the genome, which are likely responsible for the virulence of QT520. The results of genomes comparisons with strains ATCC 33843 (392 (MAV)) and ATCC 43516 showed that greater numbers genes associated with types I, II, III, IV and VI secretion systems were detected in QT520 than in other strains, suggesting that QT520 is a highly virulent strain. In addition, three plasmids were only observed in the complete genome sequence of strain QT520. In plasmid p1 of QT520, specific virulence factors (cyaB, hlyB and rtxA) were identified, suggesting that the pathogenicity of this strain is plasmid-associated. Phylogenetic analysis of 12 complete Vibrio sp. genomes using ANI values, core genes and MLST revealed that QT520 was most closely related to ATCC 33843 (392 (MAV)) and ATCC 43516, suggesting that QT520 belongs to the species V. harveyi. This report is the first to describe the complete genome sequence of a V. harveyi strain isolated from an outbreak in a fish species in China. In addition, to the best of our knowledge, this report is the first to compare the V. harveyi genomes of several strains. The results of this study will expand our understanding of the genome, genetic characteristics, and virulence factors of V. harveyi, setting the stage for studies of pathogenesis, diagnostics, and disease prevention.

【 授权许可】

CC BY