DEVELOPMENT OF A BACTERIAL BIOSENSOR FOR EARLY DETECTION OF TOXIC ALGAE BLOOMS USING SYNTHETIC BIOLOGY TECHNIQUES

HAB-related detection systems have been routinely designed based on structure-specific technologies, such as antibodies. At Kaitek Labs, we propose to shift this paradigm towards effect-based detection through bacteria and simple microorganisms, mimicking the initial idea behind mouse bioassay and biological tests.

Bacteria have a natural capacity to gather and process information about its surroundings. This computer-like function has been overlooked for many years, and never before has there been an initiative that makes use of such capacity. By giving this natural functionality both a purpose and a human interface, we can turn bacteria into information gathering machines, capable of expressing their findings to human users by simple organoleptic changes.

RTDK, or Red Tide Detection Kit, is an example of this bacterial computer or new generation biosensor approach. Using Synthetic Biology tools, our team has been capable of devising metabolic pathways that allow a cell culture to measure the amount of a certain targeted toxin in a sample, and then turn either red or blue to inform the results to the user. RTDK received a grant from the Chilean government on 2013 for its development.

Our current prototype design is based upon generating metabolic systems that act as logical gates, allowing us to operate simple AND, OR and XOR computer-like functions in simple chassis such as E. coli and S. cerevisiae. The use of this logical gates allows for a certain redundancy that makes the system more robust, associating a triple detection check to a certain target by contrast of a direct one-to-one association that could result in high amounts of false positives. The gates also allow a fine-tuning of the sensor, setting a certain detection threshold for the targeted toxins. They also interact directly with the color-changing or organoleptic routes included in the synthetic genetic circuit, effectively generating color changes that correlate with the processed information.

The prototype will be encased in a dipstick-like device, and has been developed from a design thinking perspective to be used by untrained users by basing it upon a pregnancy test's User Experience and User Interface.