Bacteria “talking” to each other – Synthetic Biologists discover new techniques

University of California San Diego biological engineers have reinvented ways bacteria talk to each other. They have found a useful tool with which they can control the bacterial action. Usually, this genetic circuit tracks down the drug delivery process, bioproduction of valuable compounds, and environmental sensing.

It discovered that bacterial communication is not possible unless there is one particular external molecule is present. This factor is the sole of this study done by San Diego researchers. The work published in Nature communication.

The first author of Nature Communication paper said this system increases the control and safety of synthetic genetic circuits and makes their application in the real-world feasible.

Conventional methods to commence bacterial communications were quorum sensing that administers the bacterial community that targets drug delivery. However, quorum sensing is the ability to respond to the cell population by gene regulation. Here the communication is possible only when there are small signaling molecules between the bacterial cells. That means the whole conversation between the bacteria, is dependent on the internal resource. To overcome this hindrance, the UC San Diego research scientist cum biologists developed this system that enables them to control the bacterial externally. It is called an inducible quorum-sensing system that will work only when a plant-derived compound called p-coumaric acid given to the bacteria. A similar to that found in the genetic circuit found in the photosynthetic bacterium Rhodopseudomonas palustris. Miano said, “The bacteria coordinate differently according to how much of the p-coumaric acid we provide in the media.” Also, if no acid provided, there is no communication between the bacteria, but if medium concentrations of acids given, there is noticeable movement and contact within them based on the size of their colony. Moreover, too much acid concentrations make them confused and overproduce signaling molecules that make them believe that they were always a part of the large population.

These students have also found a way to control bacterial cell co-ordination in time and space by co-expressing it with a lysis gene that helps in the delivery of cancer-killing drugs around a tumor.

The difference between the old and new method is demonstrated by showing how the inducible quorum sensing could control the cargo delivery system than the existent one in practice.

They preferred low and medium concentrations to study the population of bacteria in the genetic circuit and lysis gene to move in between no delivery and cargo delivery.