Jacques Dubochet, Joachim Frank and Richard Henderson were awarded 2017 Noble Prize in Chemistry for their work in developing cryo-electron microscopy (cryo-EM), a technique that fires beams of electrons at proteins that have been frozen in solution, to deduce the biomolecules structure.
Microscopes allow scientists to look at structures that cannot be seen with the naked eye – but when these structures are very tiny, it is no longer possible to use rays of light to do the job because their wavelengths are not short enough.
Instead, beams of electrons can be used – with a technique known as transmission electron microscopy (TEM) – or scientists can employ a method known as x-ray crystallography in which x-rays are scattered as they pass through samples, creating patterns that can be analysed to reveal the structure of molecules.
The trouble is, x-ray crystallography relies on biological molecules forming ordered structures, which many fail to do, and the technique does not allow researchers to probe how molecules move.
Historically, TEM also presented difficulties. The beam itself fried the biological molecules being studied, while the technique involved the use of a vacuum which resulted in biological molecules drying out and collapsing, throwing a spanner in the works when it came to probing their structure.
This year’s chemistry laureates tackled these conundrums, enabling scientists to use TEM to image biological molecules in incredible resolution.
