title: Plasmid dynamics in Vibrio parahaemolyticus strains related to shrimp Acute Hepatopancreatic Necrosis Syndrome (AHPNS).
abstract: Vibrio parahaemolyticus is a causative agent of acute hapatopancreatic necrosis syndrome (AHPNS) which causes early mortality in white shrimp. Emergence of AHPNS has caused tremendous economic loss for aquaculture industry particularly in Asia since 2010. Previous studies reported that strains causing AHPNS harbor a 69-kb plasmid with possession of virulence genes, pirA and pirB. However, genetic variation of the 69-kb plasmid among AHPNS related strains has not been investigated. This study aimed to analyze genetic composition and diversity of the 69-kb plasmid in strains isolated from shrimps affected by AHPNS. Plasmids recovered from V. parahaemolyticus strain VPE61 which represented typical AHPNS pathogenicity, strain VP2HP which did not represent AHPNS pathogenicity but was isolated from AHPNS affected shrimp and other AHPNS V. parahaemolyticus isolates in Genbank were investigated. Protein coding genes of the 69-kb plasmid from the strain VPE61 were identical to that of AHPNS strain from Vietnam except the inverted complement 3.4-kb transposon covering pirA and pirB. The strain VP2HP possessed remarkable large 183-kb plasmid which shared similar protein coding genes to those of the 69-kb plasmid from strain VPE61. However, the 3.4-kb transposon covering pirA and pirB was absent from the 183-kb plasmid in strain VP2HP. A number of protein coding genes from the 183-kb plasmid were also detected in other AHPNS strains. In summary, this study identified a novel 183-kb plasmid that is related to AHPNS causing strains. Homologous recombination of the 69-kb AHPNS plasmid and other naturally occurring plasmids together with loss and gain of AHPNS virulence genes in V. parahaemolyticus were observed. The outcome of this research enables understanding of plasmid dynamics that possibly affect variable degrees of AHPNS pathogenicity.
authors.affiliation: Department of Microbiology, Faculty of Public Health, Mahidol University, Bangkok 10400, Thailand; Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Chonchanok
authors.initials: C
authors.lastname: Theethakaew
authors.affiliation: Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan.
authors.forename: Shota
authors.initials: S
authors.lastname: Nakamura
authors.affiliation: Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Motooka
authors.affiliation: Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Matsuda
authors.affiliation: Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Kodama
authors.affiliation: Faculty of Science and Technology, Suratthani Rajabhat University, Surat Thani 84100, Thailand.
authors.forename: Kaknokrat
authors.initials: K
authors.lastname: Chonsin
authors.affiliation: Center of Ecohealth Education and Research, Faculty of Public Health, Thammasat University, Rangsit Campus, Pathum Thani 12121, Thailand.
authors.forename: Orasa
authors.initials: O
authors.lastname: Suthienkul
authors.affiliation: Department of Bacterial Infections, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan; Department of Infection Metagenomics, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan. Electronic address: iida@biken.osaka-u.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Iida
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000191:economics; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D004251:DNA Transposable Elements; D014644:Genetic Variation; D043143:Hepatopancreas / Q000473:pathology / Q000821:virology*; D033561:Penaeidae / Q000382:microbiology*; D010802:Phylogeny; D010957:Plasmids / Q000737:chemistry* / Q000378:metabolism; D014736:Vibrio parahaemolyticus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D014744:Vietnam; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements
keywords: Acute hepatopancreatic necrosis syndrome; Genetic evolution; Plasmid; V. parahaemolyticus