'Smart materials' that make proteins form crystals to boost research into new drugs

Scientists have developed a new method to make proteins form crystals using 'smart materials' that remember the shape and characteristics of the molecule. The technique, reported in the Proceedings of the National Academy of Science, should assist research into new medicines by helping scientists work out the structure of drug targets.

The process of developing a new drug normally works by identifying a protein that is involved in the disease, then designing a molecule that will interact with the protein to stimulate or block its function. In order to do this, scientists need to know the structure of the protein that they are targeting.

A technique called X-ray crystallography can be used to analyse the arrangement of atoms within a crystal of protein, but getting a protein to come out of solution and form a crystal is a major obstacle.

The number of proteins identified as potential drug targets is increasing exponentially as scientists make progress in the fields of genomics and proteomics, but with current methods, scientists have successfully obtained useful crystals for less than 20 per cent of proteins that have been tried.

Now researchers at Imperial College London and the University of Surrey have developed a more effective method for making proteins crystallise using materials called 'molecularly imprinted polymers' (MIPs). MIPs are compounds made up of small units that bind together around the outside of a molecule. When the molecule is extracted, it leaves a cavity that retains its shape and has a strong affinity for the target molecule.

This property makes MIPs ideal nucleants - substances that bind protein molecules and make it easier for them to come together to form crystals. Many substances have been used as nucleants before, but none are designed specifically to attract a particular protein.