Molecular characterization of virulence, antimicrobial and heavy metal resistance properties of Vibrio anguillarum isolated from mullet (Mugil cephalus) cultured in Korea
Molecular characterization of virulence, antimicrobial and heavy metal resistance properties of Vibrio anguillarum isolated from mullet (Mugil cephalus) cultured in Korea
- 주제(키워드) Vibrio anguillarum , Mullet , Virulence , Antimicrobial resistance , Heavy metal resistance
- 발행기관 충북대학교
- 지도교수 허강준
- 발행년도 2023
- 제출일 2023-07-10
- 학위수여년월 2023. 8
- 학위명 석사
- 학과 및 전공 일반대학원 수의학과(원)
- 원문페이지 57
- 실제URI http://www.dcollection.net/handler/chungbuk/200000771999
- UCI I804:43009-000000058622
- 본문언어 영어
- 저작권 충북대학교 논문은 저작권에 의해 보호됩니다
초록/요약
Vibrio anguillarum is the primary causative agent of vibriosis in fish, shellfish, mollusks and crustaceans. In the present study, we have focused on the exposure of mullets (Mugil cephalus) with V. anguillarum and the molecular characterization of isolated strains. We identified and characterized 22 strains of V. anguillarum from 145 samples of mullets cultured in several fish farms in South Korea. They were subjected to pathogenicity tests, antimicrobial susceptibility test, and broth dilution test to detect virulence markers, antimicrobial resistance, and heavy metal resistance properties. All the isolates showed amylase and caseinase activity, followed by gelatinase (90.9%), DNase (45.5%), and hemolysis activities (α=81.8% and β=18.2%). The PCR assay revealed that isolates were positive for VAC, ctxAB, AtoxR, tdh, tlh, trh, Vfh, hupO, VPI, and FtoxR virulence genes at different percentages. All the isolates showed multi-drug resistance properties (MAR index≥0.2), while 100% of the isolates were resistant to oxacillin, ticarcillin, streptomycin, and ciprofloxacin. Antimicrobial resistance genes, qnrS (95.5%), qnrB (86.4%), and strAB (27.3%), were reported. In addition, 40.9% of the isolates were cadmium-tolerant, with the presence of the CzcA (86.4%) heavy metal resistance gene. The results revealed potential pathogenicity associated with V. anguillarum in aquaculture and potential health risk associated with consumer health. Keywords: Vibrio anguillarum, Mullet, Virulence, Antimicrobial resistance, Heavy metal resistance
more초록/요약
Vibrio anguillarum is the primary causative agent of vibriosis in fish, shellfish, mollusks and crustaceans. In the present study, we have focused on the exposure of mullets (Mugil cephalus) with V. anguillarum and the molecular characterization of isolated strains. We identified and characterized 22 strains of V. anguillarum from 145 samples of mullets cultured in several fish farms in South Korea. They were subjected to pathogenicity tests, antimicrobial susceptibility test, and broth dilution test to detect virulence markers, antimicrobial resistance, and heavy metal resistance properties. All the isolates showed amylase and caseinase activity, followed by gelatinase (90.9%), DNase (45.5%), and hemolysis activities (α=81.8% and β=18.2%). The PCR assay revealed that isolates were positive for VAC, ctxAB, AtoxR, tdh, tlh, trh, Vfh, hupO, VPI, and FtoxR virulence genes at different percentages. All the isolates showed multi-drug resistance properties (MAR index≥0.2), while 100% of the isolates were resistant to oxacillin, ticarcillin, streptomycin, and ciprofloxacin. Antimicrobial resistance genes, qnrS (95.5%), qnrB (86.4%), and strAB (27.3%), were reported. In addition, 40.9% of the isolates were cadmium-tolerant, with the presence of the CzcA (86.4%) heavy metal resistance gene. The results revealed potential pathogenicity associated with V. anguillarum in aquaculture and potential health risk associated with consumer health. Keywords: Vibrio anguillarum, Mullet, Virulence, Antimicrobial resistance, Heavy metal resistance
more목차
I. INTRODUCTION 1
II. MATERIALS AND METHODS 4
1. Collection of fish samples and necropsy analysis 4
2. Isolation and biochemical identification of Vibrio spp 4
3. Molecular identification of V. anguillarum 5
4. Phenotypic pathogenicity tests 6
5. Detection of virulence-related genes 8
6. Antimicrobial susceptibility test 11
7. Detection of antimicrobial resistance genes 12
8. Heavy metal tolerance assay 14
9.Detection of heavy metal resistance genes 14
III. RESULTS 16
1. Identification of V. anguillarum 16
2. Determination of pathogenicity by phenotypic tests 18
3. Prevalence of virulence-related genes 20
4. Antimicrobial susceptibility pattern and MAR index 21
5. Prevalence of antimicrobial resistance genes 23
6. Heavy metal resistance properties 24
IV. DISCUSSION 27
V. SUMMERY IN KOREAN 36
VI. REFERENCES 38