title: Matrix-assisted laser desorption ionization-time of flight mass spectrometry based identification of Edwardsiella ictaluri isolated from Vietnamese striped catfish (Pangasius hypothalamus).
abstract: Edwardsiella (E.) ictaluri is a major bacterial pathogen that affects commercially farmed striped catfish (Pangasius hypothalamus) in Vietnam. In a previous study, 19 strains of E. ictaluri collected from striped catfish were biochemically identified with an API-20E system. Here, the same 19 strains were used to assess the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS; applied using a MALDI Biotyper) to conduct rapid, easy and accurate identification of E. ictaluri. MALDI-TOF MS could directly detect the specific peptide patterns of cultured E. ictaluri colonies with high (＞ 2.0, indicating species-level identification) scores. MALDI Biotyper 3.0 software revealed that all of the strains examined in this study possessed highly similar peptide peak patterns. In addition, electrophoresis (SDS-PAGE) and subsequent immuno-blotting using a specific chicken antibody (IgY) against E. ictaluri revealed that the isolates had highly similar protein profiles and antigenic banding profiles. The results of this study suggest that E. ictaluri isolated from striped catfish in Vietnam have homologous protein compositions. This is important, because it indicates that MALDI-TOF MS analysis could potentially outperform the conventional methods of identifying E. ictaluri.
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Truong Quynh
authors.initials: TQ
authors.lastname: Nhu
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Seong Bin
authors.initials: SB
authors.lastname: Park
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Si Won
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Jung Seok
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Se Pyeong
authors.initials: SP
authors.lastname: Im
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Jassy Mary S
authors.initials: JM
authors.lastname: Lazarte
authors.affiliation: Haeyeon Fish Farm, Jeju 63359, Korea.
authors.forename: Jong Pyo
authors.initials: JP
authors.lastname: Seo
authors.affiliation: BluGen Korea, Busan 48071, Korea.
authors.forename: Woo-Jai
authors.initials: WJ
authors.lastname: Lee
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea.
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Jung
mesh_terms: D000818:Animals; D002397:Catfishes; D020610:Edwardsiella ictaluri / Q000145:classification / Q000302:isolation & purification*; D004756:Enterobacteriaceae Infections / Q000175:diagnosis / Q000382:microbiology / Q000662:veterinary*; D005393:Fish Diseases / Q000175:diagnosis / Q000382:microbiology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000662:veterinary*; D014744:Vietnam
keywords: Edwardsiella ictaluri; MALDI Biotyper; Pangasius hypothalamus; identification method