Future Applications

The use of antibiotics in agriculture poses a significant threat to human health and food security. A direct link has been established between agricultural antibiotic use and developing resistances in human, plant, and animal pathogens [1]. The European Union has recently banned the use of some antibiotics in agriculture, and many countries are following suit. The development of novel antimicrobial techniques is vital to treating our agricultural crops without the risk of developing resistances. While our project focuses on a single bacterial infection, there are many different pathogens that could be countered by the same or similar techniques.

Entericidin B is a general antimicrobial peptide that is present in hundreds of bacterial species. As such, it likely has a wide range of potential targets. Because of its proven efficacy against F. psychrophilum, it is likely that our developed treatment will also effectively combat other fish pathogens of the genus Flavobacterium. One such bacteria (Flavobacterium coulumnaris) was recently responsible for a 95% die-off of salmonids at an Oregon hatchery [2]. Our treatment could have prevented this and similar hatchery pandemics caused by various Flavobacterium species.

If the Entericidin B peptides utilized in our project aren’t effective against a specific bacteria, the same system utilizing a different agent could be utilized. Antimicrobial peptides are ubiquitous and have naturally developed as an innate immune response in many organisms [3]. These peptides have distinct advantages over traditional antibiotics including broad spectrum activity and a lower chance for increased resistance [3]. While these peptides cost more to produce and are susceptible to proteolysis, they could be used much more safely [3]. The increased degradation could even be beneficial for agricultural applications as less antimicrobial agent would make it into our food and waterways.

We have also identified multiple other bacterial infections that could be targeted using antimicrobial peptides. For example, cystitis, a disease among cattle caused by species of Listeria and Escherichia, causes beef loss and could theoretically be preempted through administration of an antibacterial toxin similar to Entericidin B. This and other livestock diseases may become more widespread as more countries move away from traditional antibiotics; utilizing antimicrobial peptides could help alleviate this issue.

Antibacterial toxins can also be employed to combat plant diseases of economic significance. For instance, bacterial stalk rot and Stewart’s disease, both devastating diseases of maize, could theoretically be addressed through the utilization of an antibacterial toxin, delivered through crop dusting. Other potential agricultural solutions abound.

While admittedly more ambitious, oral probiotics could be used in the future to treat human infectious diseases. There have been multiple medical trials of antimicrobial peptides for use in humans, but to our knowledge none of these have been FDA approved [3]. Some of these trials have been promising, and it is likely that antimicrobial peptides will become a regular agent in human health in the near future as research moves away from traditional antibiotics.

Future applications for fishBIT, our a novel solution for drug delivery in fish, are numerous. While it is a great method for delivering flavocide to sick fish, we at fishPHARM believe in always challenging ourselves to find the most innovative solutions. While working on a formula and dosing for flavocide is our number one priority, we will continue to explore new ways of delivering the time-released medication to affected fish. One possible future method of flavocide delivery would be a pneumatic injection system. This system injects individual capsules in fish for rapid and accurate delivery. This system would make treating fish a much less time-consuming process, and would increase the appeal of the fishPHARM BCWD treatment method.

In short, we have developed a theoretical means of curing bacterial diseases that does not rely on antibiotics. This is a highly valuable characteristic in times of increased antibiotic resistance among pathogens. We believe that our treatment method could be directly applied to multiple bacterial infections. The technique we’ve employed to utilize small antimicrobial peptides to treat disease can be applied to the agriculture and human health. With increased antibiotic resistance a growing problem, solutions such as ours will have a more prominent role in human health and food security.

References

[1] Witte, W. (1998). BIOMEDICINE: Medical Consequences of Antibiotic Use in Agriculture. Science, 349(6253), 996-997.

[2] House, K. (2015). Disease kills 150,000 fish in hatchery's 2nd major die-off this year. The Oregonian. URL: http://www.oregonlive.com/environment/index.ssf/2015/08/disease_kills_150000_fish_in_h.html

[3] Gordon, Y., Romanowski, E., & Mcdermott, A. (n.d.). A Review of Antimicrobial Peptides and Their Therapeutic Potential as Anti-Infective Drugs. Curr Eye Res Current Eye Research, 30(7), 505-515.