One division of synthetic biology combines natural parts to create something unique, like our glowing plant project which combines the glowing protein from a firefly with a traditional plant. This seems to be an obvious first step in synthetic biology, because nature has already produced so many incredible proteins and biological mechanisms. By separating nature into several standardized parts, those parts can be combined in intelligent ways to produce novel functions.
Another, perhaps more difficult component to synthetic biology is improving natural parts. Life on earth has developed for roughly 3.6 billion years via natural selection through mutation, how could a species which has survived for only a small fraction of that time improve biological function?
Researchers at the University of California, Los Angeles have done just that, by engineering the metabolic pathway known as glycolysis to be more efficient. Glycolysis is a process which occurs in nearly all organisms, which produces energy from sugars. It is a fairly efficient pathway, but its small inefficiencies repeated perpetually by copious amounts of small organisms are the major source of carbon loss in biorefining and microbial carbon metabolism. Synthetic non-oxidative glycolysis enables complete carbon conservation in sugar catabolism, and could potentially be used in conjunction with other pathways to accomplish a 100% carbon yield to fuels and chemicals (Laio, 2013).
This research is truly incredible for a number of reasons; humans were able to improve upon a biological process which has existed for as long as 2 billion years, small organisms used as biological machines will become more efficient, and because I conceived of the idea to improve these pathways several years ago in my biochemistry course (without a clue for how accomplish this task).
At Genome Compiler we are developing software capable of determining the most efficient pathway to convert a chemical into any other chemical, using naturally occurring enzymes. One can then purchases the DNA sequence which produces the enzyme pathway, order it in a small circular genome called a plasmid, and insert it into a host organism such as bacteria or yeast. There will be some difficulties in this process; like coercing the organism to prioritize your synthetic pathway rather than their natural pathways. Nevertheless, this appears to be a more efficient method to produce a molecule, compared to traditional chemical reactions.
Combining the innovation of natural biological variation with the ingenuity of human thought through computing power will produce a wave of inexpensive small molecules. Soon the question will shift from how to produce these molecules (like biofuels and pharmaceutical drugs), to what molecules should we produce to improve human health and solve environmental concerns. I look forward to this change in mindset.
Bogorad, I., Lin, T. and Liao, J., 2013. Synthetic non-oxidative glycolysis enables complete carbon conservation. Nature 502: (693-698)