One of the overwhelming problems that synthetic biologists face on a daily basis is the variability in genetic constructs. With our ever persistent drive to find a way to develop a standard set of parts for synthetic biology, it is often overlooked that these “standard” parts do not interact the same way that a nut and a bolt do. Sure the threads of each must match for compatibility, but you are guaranteed that a matching set of nuts and bolts will hold together a table just as well as they will hold together a chair, or a piece of metal machinery, or the engine of your car.

When we place together a promoter with a new gene of interest we do not yet have these compatibility rules to know how a promoter will work with this gene of interest. We, as synthetic biologists, still don’t know that one promoter/gene will work the same way in one strain of E. coli as they will in another E. coli. For synthetic biology to truly emerge as a field that can capitalize in industry, we must find novel ways of engineering biological systems reliably using our own standard parts.