Isolation of a lytic bacteriophage against virulent Aeromonas hydrophila from an organized equine farm.

The research identifies a bacteriophage called VTCCBPA6 which fights against a harmful strain of Aeromonas hydrophila, found in the sewage of an equine breeding farm. The bacteriophage shares characteristics with T4-like virus genus and shows potential to be used as a biocontrol agent.

Research Objectives

• The study aimed at isolating a bacteriophage, termed as VTCCBPA6, against a harmful strain of Aeromonas hydrophila.
• It also sought to study the phylogenetic resemblance of the isolated phage by analysing the gp23 gene responsible for encrypting the major capsid protein.
• Furthermore, the research aimed to compare the phage’s gp23 gene sequence with previously known phages and determine its similarity.

Methodology and Findings

• The bacteriophage was isolated from the sewage of an organized equine breeding farm. This environment provided the characteristic breeding ground for this microorganism.
• Upon analysis using Transmission Electron Microscopy (TEM), the phage was classified under the Myoviridae family. These are a group of viruses known for their long, contractile tails.
• PCR amplification and sequence analysis of the gp23 gene revealed its phylogenetic resemblance to the T4-like virus genus, indicating that the bacteriophage belongs to the same group of viruses.
• Protein profiling was performed using SDS-PAGE analysis, solidifying its resemblance to the T4-like phage group.
• The comparison of the gp23 gene sequence with previously reported phages interestingly showed similarity with T4-like phages infecting Enterobacteriaceae rather than Aeromonas spp. This finding underlines the possibility of a novel or evolved phage in the equine environment that counteracts A. hydrophila.

Implications of Findings

• The isolated bacteriophage presents a potential to be utilized as a biocontrol agent. This is primarily because of its ability to fight against Aeromonas hydrophila, a pathogenic bacterium known to cause diseases in fish, reptiles, and amphibians, and sometimes in humans.
• The study could serve as an important first step towards understanding the interaction of this particular phage with the ecosystem, and how it could be harnessed for biocontrol purposes.
• The similarity found with T4-like phages infecting Enterobacteriaceae, and not Aeromonas spp., suggests that there might be a novel or evolved phage against A. hydrophila in the equine environment. This discovery may lead to novel insights into the physiology and ecology of these microorganisms, giving way to new advancements in microbial control.