Many futurists have predicted the 21st century to be the century of biology. In fact, the successful sequencing of the human genome has allowed a new field of biology to flourish: synthetic biology. This pioneering discipline has the objective goal of constructing biological systems to serve a useful purpose.
Synthetic biology yields many applications that would have seemed near-impossible just a few decades ago; from energy generation and food production, to directed evolution by creating biological circuits through cell transformations, and even a cutting-edge means of information storage.
This wave of recent innovation has inspired a group of researchers in Singapore, who have utilised synthetic biology to engineer bacteria that can seek out and destroy pathogens. This bacteria is a less harmful strain of Escherichia coli (E. coli), which is able to detect and immediately break down biofilms. To add to this exciting break-through, the researchers have full confidence that their engineering methods can be applied to not only target biofilms, but other pathogens as well.
Biofilms are groups of microbial cells that assemble and adhere to aqueous surfaces, forming an extracellular polymeric substance matrix. These cells currently are a major problem in the field of medicine. Their sugar and protein-rich sheets provide refuge for pathogens inside the body as well as on medical implants; making several diseases harder to target and treat with conventional therapies such as antibiotics.
This ongoing problem has motivated these researchers to search for alternative treatments; specifically, re-programming E. coli to sense Pseudomonas aeruginosa (a pathogenic and biofilm-enclosed bacterium).
Dr Matthew Chang, leading the research group, re-programmed E. coli to release an antimicrobial peptide that is able to degrade biofilms. It is important to note that P. aeruginosa biofilms are also heavily comprised of DNA, which hold much of the bacteria together. This lead Dr Chang to arm his E. coli with the enzyme DNase I, which breaks the biofilm by attacking its DNA links.
But Dr Chang did not just stop there, he further allowed his E. coli to recognise P. aeruginosa cell signalling; thus allowing the E. coli to attack before the P. aeruginosa even has a chance to combine with nearby cells.
These are exciting times we live in, where synthetic biology could usher in novel therapies; leading to more localised and precise treatments when targeting pathogens.