June 1, 2010

Spanish scientists develop aquaculture-disease-control biosensor

A team of Spanish scientists at the University of Granada (UGR) are working on the development of a biosensor that allows for the long-term control of the virulence of some marine bacteria and halophiles responsible for the appearance of pathogenic diseases in farmed fish and molluscs.

The biosensor is based on the system denominated quorum sensing, that allows the bacteria to communicate through molecular signals.

The particularity of this intercellular bacterial communication system is its production when 'there is quorum,' that is, it requires the production of a great number of these molecules for the correct operation of this system, said the researchers, who used the strain Halomonas anticariensis to build the biosensor.

One of the main characteristics of the bacterium is that it grows in highly varied saline concentrations, from a low concentration of sodium chloride (table salt) to extreme salinities.

"In particular, we want to verify if the pathogenic mechanisms of the bacteria that affect fish and molluscs in hatcheries are activated by means of this system," the scientists added.

Once they have demonstrated this, the experts will tackle the development of new antimicrobial compounds that interfere with the quorum sensing of the bacteria, in a bid to battle the infections that hatchery fish and molluscs suffer from.

The aquaculture species become ill due to the inefficiency of some vaccines and restricted antibiotics use.