Aeromonas species obtained from different farmed aquatic species in India and Taiwan show high phenotypic relatedness despite species diversity

Saurabh Dubey; Biswajit Maiti; Shivani Kallappa Girisha; Rakesh Das; Mustapha Lamkhannat; Stephen Mutoloki; Shih-Chu Chen; Indrani Karunasagar; Øystein Evensen; Hetron M Munang Andu

doi:10.1186/s13104-021-05716-3

Aeromonas species obtained from different farmed aquatic species in India and Taiwan show high phenotypic relatedness despite species diversity

BMC Res Notes. 2021 Aug 16;14(1):313. doi: 10.1186/s13104-021-05716-3.

Affiliations

¹ Faculty of Veterinary Medicine, Norwegian University of Life Sciences, P.O. Box 369, 0102, Oslo, Norway.
² UNESCO MIRCEN for Medical and Marine Biotechnology, Nitte University Centre for Science Education and Research, NITTE (Deemed to be University), Paneer Campus, Deralakatte, Mangalore, 575018, India.
³ Department of Fisheries Microbiology, Karnataka Veterinary, Animal & Fisheries Sciences University, College of Fisheries, Mangalore, 575002, India.
⁴ ICAR-Central Institute of Freshwater Aquaculture (CIFA), Kausalyaganga, Odisha, 751002, India.
⁵ Department of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, Taiwan.
⁶ Faculty of Veterinary Medicine, Norwegian University of Life Sciences, P.O. Box 369, 0102, Oslo, Norway. hetroney.mweemba.munangandu@nmbu.no.

Abstract

Objectives: Aeromonads cause severe diseases in farmed aquatic organisms. Herein, we examined 28 isolates causing disease in farmed aquatic organisms from India (n = 24) and Taiwan (n = 4) to gain insight of their genotypic and phenotypic properties.

Results: API 20NE biochemical phenotyping showed ≥ 90% similarity classifying all isolates as Aeromonas hydrophila. 16S rRNA genotyping showed ≥ 98% homology among all isolates with A. sobria (NR119044.1ATCC), A. veronii (MK990549.1), A. caviae (NR029252.1) and A. hydrophila (MG984625.1ATCC) and other reference strains. In contrast, gyrB showed a higher intraspecies diversity (≥ 96%) than 16S rRNA delineating the 28 isolates into three groups. Group-I consisted of seven Indian isolates clustered with A. sobria (MK484163.1ATCC), group-II comprised of five Indian and two Taiwanese isolates clustered with A. veronii AF417626.1ATCC while group-III had 11 Indian and three Taiwanese isolates grouped with A. hydrophila (AY987520.1 and DQ519366.1) reference strains. None of our isolates clustered with A. caviae (AJ868400.1ATCC) reference strain. These findings suggest that A. sobria, A. veronii and A. hydrophila could be the etiological agents of diseases observed in farmed fish and soft-shelled turtles (Pelodiscus sinensis) examined in this study. Overall, our findings accentuate the importance of combining phenotyping with genotyping for correct taxonomic classification of Aeromonas spp. in Aquaculture.

Keywords: 16S rRNA; A. sobria; A. veronii; Aeromonas hydrophila; Genotype; Phenotype; gyrB.

MeSH terms

Aeromonas hydrophila / genetics
Aeromonas* / genetics
Animals
India
RNA, Ribosomal, 16S / genetics
Taiwan

Substances

RNA, Ribosomal, 16S

Grants and funding

239140/Norges Forskningsråd