DOI QR코드

DOI QR Code

Shewanellasp., A Potential Pathogen of White Leg Shrimp Cultured in Low Salinity Water in Korea

국내산 저염분 양식 흰다리새우 유래의 슈와넬라의 병원성 세균으로의 특성

  • Jin Woo Jun (Department of Aquaculture, Korea National University of Agriculture and Fisheries)
  • 전진우 (국립한국농수산대학교 수산양식전공)
  • Received : 2023.09.18
  • Accepted : 2023.10.13
  • Published : 2023.10.30

Abstract

White leg shrimps cultured in an inland private aquaculture farm with low salinity waters showed abnormal swimming behavior and appetite reduction in July 2022. Then, gradual mortality was observed in the aquaculture farm. During the diagnosis, bacterial strain KNUAF-SHP3 was isolated from the hepatopancreas of the dead shrimps. Based on the sequence of 16S rRNA gene, KNUAF-SHP3 was proved to be Shewanella sp., clustering into a group with S. algae MARS 14 and S. chilikensis JC5T. According to the result of experimental infection test, all shrimps challenged with high concentrations, 2.1×108 CFU/ml and 2.1×109 CFU/ml showed apparent disease symptoms and the cumulative mortality rates reached 100% in 7 days post challenge. These results emphasized that Shewanella isolate in this study can be a potential pathogen of white leg shrimp cultured in low salinity water.

2022년 7월, 국내의 저염분 해수 흰다리새우 양식장에서 양식 중이던 흰다리새우가 이상유영과 식욕부진을 보이며 지속적으로 폐사하였다. 일일 평균 폐사율이 0.1%로 완만한 폐사를 보였으나, 2달 넘게 폐사가 지속되었고 성장 지체로 인한 경제적인 피해가 가중되었다. 질병 진단 과정 중, 폐사 새우의 간췌장에서 세균(KNUAF-SHP3)이 분리되었다. 본 세균의 16S rRNA 유전자의 시퀀스 분석 결과, 분리주 KNUAF-SHP3은 Shewanella에 속하는 균으로 동정이 되었고, S. algae MARS 14, S. chilikensis JC5T와 근연 관계를 보이며 같은 그룹으로 분류되었다. 실험 동물을 활용한 인위 감염 실험에서는 상대적으로 고농도(2.1×108CFU/ml와 2.1×109CFU/ml)를 적용한 군에서는 모든 새우들이 감염 증상을 보이며 감염 후 7일 내에 100% 폐사율을 나타내었다. 본 연구는 Shewanella 세균이 저염분 해수 양식 흰다리새우에서의 잠재적인 기회 감염균이 될 수 있음을 기술하고 있다.

Keywords

References

  1. Cai J, Chen H, Thompson KD, Li C. (2006). Isolation and identification of Shewanella alga and its pathogenic effects on post-larvae of abalone Haliotis diversicolor supertexta. J Fish Dis 29: 505-508. https://doi.org/10.1111/j.1365-2761.2006.00732.x
  2. Hall TA. (1999). BioEdit: A user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symp Ser 41: 95-98.
  3. Larkin MA, Blackshields G, Brown NP, et al. (2007). Clustal W and Clustal X version 2.0. Bioinformatics 23: 2947-2948. https://doi.org/10.1093/bioinformatics/btm404
  4. Martin-Rodriguez AJ, Suarez-Mesa A, Artiles-Campelo F, Romling U, Hernandez M. (2019). Multilocus sequence typing of Shewanella algae isolates identifies disease-causing Shewanella chilikensis strain 614. FEMS Microbiol Ecol 98: fiy210.
  5. Prachumwat A, Wechprasit P, Srisala J, Kriangsaksri R, Flegel TW, Thitamadee S, Sritunyalucksana K. (2020). Shewanella khirikhana sp. nov. - a shrimp pathogen isolated from a cultivation pond exhibiting early mortality syndrome. Microb Biotechnol 13: 781-795. https://doi.org/10.1111/1751-7915.13538
  6. Roy LA, Davis DA, Saoud IP, Boyd CA, Pine HJ, Boyd CE. (2010). Shrimp culture in inland low salinity waters. Rev Aquac 2: 191-208. https://doi.org/10.1111/j.1753-5131.2010.01036.x
  7. Tamura K, Stecher G, Kumar S. (2021). MEGA11: molecular evolutionary genetics analysis version 11. Mol Biol Evol 38: 3022-3027. https://doi.org/10.1093/molbev/msab120
  8. Zhou H, Gai S, Ye G, An J, Liu K, Xu L, Cao H. (2019). Aeromonas hydrophila, an emerging causative agent of freshwater-farmed whiteleg shrimp Litopenaeus vannamei. Microorganisms 7: 450.
  9. Zhu S, Zhang C, Wu H, Jie J, Zeng M, Liu Z, Wang C, Yang H. (2017). Spoilage of refrigerated (4 ℃) Litopenaeus vannamei: cooperation between Shewanella species and contribution of cyclo-(L-Pro-L-Leu)-dependent quorum sensing. Int J Food Sci Technol 52: 1517-1526. https://doi.org/10.1111/ijfs.13427