The Guardian view on protein modelling: the answer to life, the universe and everything | Editorial
When Eliezer Yudkowsky, one of the world's top artificial intelligence theorists, mused about how superintelligent robots might wipe out humans he speculated that perhaps they would solve one of the science's holy grails: predicting protein structure from DNA information. In Mr Yudkowsky's words these robots would then "synthesise customised proteins ... building even more sophisticated molecular machines. Imagine tiny invisible synthetic bacteria, with tiny onboard computers, hiding inside your bloodstream and everyone else's. And then, simultaneously, they release one microgram of botulinum toxin. Everyone just falls over dead." Mr Yudkowsky's apocalyptic scenario rests on something science has pondered with no answer for decades: why can't we say what determines a protein's shape?
This is not some idle speculation. Proteins are the bedrock of living systems, intimately involved in every physiological process from triggering an immune response to thinking. Good health requires a fine balance of proteins. An imbalance, and disease often strikes. Cancer is traced to an overproduction of proteins. Misfolding proteins have been linked to type 2 diabetes, while the strange bundling of them is thought to be behind the death of brain cells in Parkinson's disease. Proteins' function is dependent on their form, which is the result of a folding up of hundreds of amino acids - its constituent parts - into a specific and complex 3D structure. That configuration determines what the protein does: whether it becomes an enzyme to accelerate a chemical reaction; or a receptor passing signals to a cell's molecular machinery. Crucially, a drug can alter a protein's function by binding to it in a particular spot. Designing medicines to target diseases requires knowing what proteins are involved and their form. After a half century we can identify 100,000 protein shapes. But we have a database of 100m proteins. That is why we have few molecular keys capable of picking the lock to understanding disease-causing proteins.
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