title: A silkworm infection model to investigate Vibrio vulnificus virulence genes.
abstract: The halophilic marine bacterium, Vibrio vulnificus, occasionally causes fatal septicemia in immunocompromised patients. Mice are commonly used as experimental animals to investigate the virulence of V. vulnificus, however, a large number of mice are generally required for bioassays. The present study examined whether the invertebrate species, silkworms, can be used instead of mice to investigate V. vulnificus virulence. When the silkworms were inoculated with 1.2x107 colony forming units of V. vulnificus OPU1‑Rf, a virulent strain of V. vulnificus, all injected silkworms died within 48 h, however, those injected with culture filtrate or diluent did not. This silkworm infection model was then used to isolate attenuated V. vulnificus mutants from 1,016 transposon‑inserted mutants. Consequently, a harmless mutant, SW998, was isolated. In this strain, the transposon was inserted into the rtxA gene, which is a known V. vulnificus virulence gene. In conclusion, the present study demonstrated that silkworms are useful animals for investigating the virulence of V. vulnificus.
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: School of Veterinary Medicine, Kitasato University, Towada, Aomori 034‑8628, Japan.
authors.forename: Takashige
authors.initials: T
authors.lastname: Kashimoto
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Yoshimura
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Tachibana
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Shiho
authors.initials: S
authors.lastname: Kuroda
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Miki
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Sou
authors.initials: S
authors.lastname: Kitabayashi
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Ping
authors.initials: P
authors.lastname: Tong
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Xiao
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo‑ku, Tokyo 113‑0033, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hamamoto
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo‑ku, Tokyo 113‑0033, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Sekimizu
authors.affiliation: Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719‑1197, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D012831:Bombyx / Q000254:growth & development / Q000382:microbiology*; D004251:DNA Transposable Elements / Q000235:genetics; D004195:Disease Models, Animal; D006801:Humans; D051379:Mice; D018805:Sepsis / Q000235:genetics / Q000382:microbiology* / Q000473:pathology; D041261:Vibrio vulnificus / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*
chemical_list: D004251:DNA Transposable Elements