Synthetic biology is a new area of biological research that combines biology and engineering in order to design and build ("synthesize") new biological functions and systems in cells.
The controversial scientist Craig J Venter and his team built the first synthetic organism “Synthia” last year after 10 years of research. They took a commonly occurring bacterium, stripped out its genome (DNA) and then replaced it with their own synthetic DNA produced in the lab. Although these synthetic cells had only just enough genetic material to allow it to survive, this amazing achievement is proof that genomes can be designed by a computer, made in the laboratory and transplanted into a recipient cell to produce a new self-replicating cell controlled only by the synthetic genome.
But why would anyone want to create an artificial cell? Well the aim is to take a cell that has the basic function necessary for it to ‘live’ and then ‘add’ new features to it, allowing it to produce specific products. Sounds complicated, but it starts to make sense when you look at it like this.
In synthetic biology you can think of a cell almost like a computer: in a computer, there are a whole lot of individual parts, like memory, CPUs, and video cards, which work together to provide different functionalities. In cells, there are also a lot of different parts – things called membranes, mitochondria, ribosomes, enzymes etcetera – that work together, providing different functions to make the whole cell work.
All of these different parts are coded for by the cell’s genetic material, DNA, the same way computer programs have code to make them work. And in the same way we use different bits of code in different computer programs, we can also use different bits of DNA to program a cell. We call these bits of DNA ‘BioBricks’.
These bio-bricks code can then be connected like computer circuitry inside the cell by a Synthetic Biologist. These codes can then be arranged inside a modified bacteria or yeast cell that has had most of its natural genetic material or production lines removed – just like an empty factory. The genetic plans for the new production line can then be installed inside the chassis cell and the brand new cell factory will then be ready for operation.
But what makes synthetic biology different from plain old genetic engineering? Well, in genetic engineering, a few genes might be added or deleted from a cell, but these genes already exist in nature. In synthetic biology, we are making biological parts and devices that don’t already exist in nature: either extensively modifying existing DNA code, or creating entirely new bits of code that produce new components. This is like writing a new program for the cell and getting it to work properly with existing DNA and cell parts.
This difference between synthetic biology and genetic engineering is as subtle as it is profound. Synthetic engineering is effectively the creation of life through totally artificial means. For some this might sound scary, but the reality is there are many aspects of this process that are still quite natural. Because of our large size, complex cellular structures and sentient qualities we often over look the fact that the organic life around us exists because at the smallest scale, each atom inside us obeys of the fundamental laws of chemistry and physics. Artificially created or not, organic life will only exist if its base components are arranged in a similar way to what we would expect in any naturally occurring system.
As yet, we’ve not seen synthetic biology used as a plot device for a Hollywood film- probably due to it only being an emerging technology. Genetic engineering however has had a great run in the horror genre, responsible for everything from disease epidemics, mutant creatures and the return of the dinosaurs. As far as synthetic biology goes FLUBBER may well qualify as a product of artificial life- can anyone out there think of another film with a star that qualifies?
But back on topic- so what might synthetic biology used for? One example is creating cells that produce special hi-tech products that humans can harvest and use. Currently Synthetic Biologists are exploring ways to make low cost drugs that will overcome global shortages for diseases such as malaria. They are also investigating ways to turn sugar cane into jet fuel and create super fibres like spider silk.
Artificial organisms produced with these techniques could be used to alert us to the presence of environmental toxins, produce carbon neutral fuel sources, create super strong/super light textiles and help us diagnose and protect us from disease. Right now however, there is still a lot to learn because although we know how to read and write the genetic code, we still don’t know how to use it to solve a particular problem.
But as we learn more about synthetic biology we will be able to design more complicated cell systems and tackle many of the problems facing our modern world today. In theory, the uses and applications of Synthetic Biology are only limited by our imagination.
Watch FiST Chat 48: Synthetic Biology & Biotechnology for more on this topic.