Animal-sourced insulin was once the only available source of medication for diabetics. Then genetic breakthroughs and synthetic biology gave rise to the wholesale production of insulin. A revolution of similar ilk may be just around the corner. A research team from the University of Manchester has created a machine capable of synthesising short segments of protein.
This machine mimics the protein workhouses already present in living organisms, called ribosomes. These are the molecules that read our genetic information, and generate the proteins which make up everything in our bodies from building blocks, called amino acids. This nano-machine is, however, currently far from superseding nature. At just a few millionths of a millimeters across, and working at the pace of a sedated snail – it completes a single step in the time it would take a ribosome to do 864,000 – the much more simplistic protein-builder is, however, an exciting step towards synthesising the molecules we need, be they proteins, drugs, or whatever, in a whole new way.
Unlike what genetic engineering did for insulin, the nano-machine Professor David Leigh’s team in Manchester has created is unlikely to develop into something that can compete with the industry’s current protein and drug synthesis techniques, at least in terms of efficiency and quantity. What it might be able to do is enable scientists to create much more intricate molecules in a manner equal to and perhaps exceeding the breadth of creation that ribosomes accomplish (and these are the things that make every protein in your body!). This is because, unlike ribosomes, such nano-machines are not limited by the building blocks upon which life depends – they do not have to construct exclusively from amino acids, bases or carbohydrates, which we are made of.
Nano-machines like Professor Leigh’s – which I’m going to go ahead and dub ribots (couldn’t resist) – may ultimately be used to create drugs and plastics with exquisitely intricate structures, enabled by the high level of control and specificity ribots can give their engineers. Specific sequences can be dictated and translated without the age-old chemistry of step-by-step reactions. Final, complex products could be synthesised from their constituents in the same reaction vessel without the tedium of preparing sequential reactions and putting intermediaries through rounds and rounds of purification. In other words, it might just be that we’ll see ribots producing the Lamborghinis of the synthetic molecular world: rarer, slower to make, but more specialised.
If their rate and complexity of production could be improved, ribots may also have novel and intriguing medical applications. If, for example, you had a genetic condition brought on by a symptomatic, molecular deficiency, ribots, of quite a different nature to Professor Leigh’s, could invade cells and make use of the cells’ materials in the same way as ribosomes, but with a greater scope. They may then act to produce the deficient molecule and mitigate or eliminate the detrimental effects of an underlying condition. For example, they might synthesise important neurotransmitters for synaptic transmission and so mitigate some of the effects of conditions like depression, in a similar way to antidepressant drugs. Ribots could also act like gene therapies to replace a mutant protein with a normal one.
I might be firing in the dark here, and we’re currently a far way off from the possibilities that I have outlined above. Nevertheless, Professor Leigh’s team hopes to improve on their creation by developing ribots capable of grabbing constituents from the relative chaos of a flowing fluid. Such an improvement could open the door for ribots that could work in organic settings by creating proteins to influence a cell in situ. Enter the age of ribotics? Perhaps not quite, at least not yet, still, this research does expose a whole new way of looking at how we make our molecules.