Aquaculture and Vibrios

Vibrios are gram negative, curved and rod shaped, microbes which are most commonly found in coastland and estuarine waters which are natural inhabitants of the marine environment. Many groups are free living though some can form pathogenic or symbiotic interactions with eukaryotic hosts and often alternate between growing within the host or prolonged survival within aquatic habitats. In vibrios such as these it is the ability to form and maintain a biofilm mode of living that is key to their survival and transmission. Growing as a biofilm is the preferred way of growth for alot of microbial life as it enhances the growth of the microbes that form the biofilm as they have better access to nutrients. It also increases the survival rate of the microbes by providing protection against predators and antimicrobial agents. Vibrio biofilms are a particular problem for aquaculture as they can infect the fish stocks relatively quickly and transmit across the stocks quickly.

This study focussed on the effect that the supernatant of marine bacterial culture has upon the biofilm formation of vibrio sp. The authors screened samples of vibrio sp for biofilm inhibitors and then used light microscopy in order to observe and document the biofilms as they developed. After running intial attachment assays and Bacterial Adhesion To Hydrocarbons (BATH) assays upon cultures it was found that bacterial culture supernatants of Bacillus pumilus (S8-07) and Bacillus indicus (S6-01) were able to destroy the architecture of the biofilm and reduced the surface hydrophobicity of the vibrio sp. which is an essential requirement for biofilm formation. The paper concludes with the suggestion that the two strains previously mentioned could also be used to control the proliferation of vibrio biofilms in aquaculture.

Nithya C., Pandian SK., 2010, The in vitro antibiofilm activity of selected marine bacterial culture supernatants against vibrio spp, Archives of microbiology, 192, 843-854