Skip to main content
ARS Home » Southeast Area » Auburn, Alabama » Aquatic Animal Health Research » Research » Publications at this Location » Publication #417918
Research Project: Integrated Research to Improve Aquatic Animal Health in Warmwater Aquaculture

Location: Aquatic Animal Health Research

Title: Novel Lytic Bacteriophage AhFM11 As An Effective Therapy Against Hypervirulent Aeromonas hydrophila

Author
item SANKAPPA, NITHIN - Orise Fellow
item KALLIHOSURU, BOREGOWDA - Karnataka Veterinary, Animal And Fisheries Sciences University
item MANDRIRA, RAMACHANDRA - Karnataka Veterinary, Animal And Fisheries Sciences University
item SHIVANI, KALLAPPA - Karnataka Veterinary, Animal And Fisheries Sciences University
item KATTAPUNI, SURESH - Karnataka Veterinary, Animal And Fisheries Sciences University
item SHRIRAJE, BALAKRISHNA - Karnataka Veterinary, Animal And Fisheries Sciences University
item BALLAMOOLE, KRISHNA - Karnataka Veterinary, Animal And Fisheries Sciences University
item THANGAVEL, SURESH - Karnataka Veterinary, Animal And Fisheries Sciences University
item SAHOO, LOPAMUDRA - Karnataka Veterinary, Animal And Fisheries Sciences University
item Lange, Miles
item Deshotel, Michael
item Abernathy, Jason

Submitted to: American Fisheries Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/11/2024
Publication Date: 4/11/2024
Citation: Sankappa, N.M., Kallihosuru, B.K., Mandrira, R.N., Shivani, K.G., Kattapuni, S.P., Shriraje, B.D., Ballamoole, K.K., Thangavel, S., Sahoo, L., Lange, M.D., Deshotel, M.B., Abernathy, J.W. 2024. Novel Lytic Bacteriophage AhFM11 As An Effective Therapy Against Hypervirulent Aeromonas hydrophila [ABSTRACT]. American Fisheries Society Fish Health Section Seminars 2024, Webinar, July 11, 2024.

Interpretive Summary:

Technical Abstract: Numerous farmed fish species, such as carps, tilapia, salmon, and catfish, have faced considerable economic losses in aquaculture due to motile Aeromonas septicemia caused by Aeromonas hydrophila. Phages infecting hypervirulent Aeromonas hydrophila (vAh) had not been isolated anywhere in the world; however, phages have been isolated against motile Aeromonas septicemia (MAS) with only few of them having been characterized. This study aimed at developing therapeutic phage against hypervirulent Aeromonas hydrophila infection in aquaculture systems. A total of 110 water samples were collected aseptically. A novel phage AhFM11 specific to hypervirulent A. hydrophila was isolated and shows lytic activity against reference A. hydrophila (ATCC 35654). Soft agar overlay method was used to determine titer and found to be 1.58 x 1010 pfu/mL. Host range of the AhFM11 phage was performed for 131 Aeromonas spp. and 10 non Aeromonas. The results indicated that AhFM11 had a broad host range, infecting 65 Aeromonas species. Also, it was found that this phage did not harbor any antibiotic resistance genes. We isolated and characterized a novel lytic bacteriophage, AhFM11, which infects hypervirulent Aeromonas hydrophila (vAh). This is the first documented instance of a phage against vAh. Phage AhFM11 showed lytic activity against both vAh strains and the A. hydrophila reference strain ATCC 35654. The genome of AhFM11, consisting of 168,243 bp with an average G+C content of 41.5%, was sequenced and assembled, revealing no antibiotic resistance genes. Genomic data and transmission electron microscopy classified AhFM11 as belonging to the Straboviridae family. Therapeutic application of AhFM11 in fish resulted in 100% survival following injection, 95% survival via immersion, and 93% survival through oral administration with phage-coated feed. These results suggest that phage AhFM11 could serve as an effective biocontrol agent against vAh, offering an alternative to antibiotics in aquaculture.