Crystals of a DNA repair protein

The twentieth century will be remembered for many scientific achievements: the discovery of DNA, the invention of antibiotics, man landing on the moon; but none of this would have been possible were it not for one vital and relatively unknown technique: crystallography.
 

Crystallography is the unsung hero of science. It refers to the process of freezing materials - like a drop of river water or a virus - into a crystal. Crystallising something causes its structure to become symmetrical, like a snowflake. Once crystallised, scientists shine X-rays through the sample; the atoms inside the crystal absorb light, creating a shadow effect called a diffraction pattern, and scientists can use this pattern to determine the atomic structure of the material.

 

Crystallography has revolutionised modern science, allowing us to uncover the world at the atomic level. It has driven modern medicine, engineering and technology, and will undoubtedly remain at the forefront of advances in the future. To celebrate science’s hidden gem, the United Nations has declared 2014 the International Year of Crystallography. This year marks 100 years since crystallography leaped onto the scene, and it all started with two men named Bragg.

 

In 1912, William Henry and son Lawrence were busy firing X-rays at crystals of salt. X-rays had been discovered 300 years earlier and still no-one was quite sure what they were. Earlier that year, a German physicist named Max Von Laue had found that X-ray light, when shone through a crystal, diffracted in a beautiful pattern. Months later, the Braggs were busy mimicking Von Laue’s experiment and trying to pin down the mysterious rays.

 

It was during these experiments that the Braggs realised that the light and dark spots produced through X-ray diffraction were related to the arrangement of atoms inside the crystal. They used the pattern to create a mathematical formula, Bragg’s Law, which showed how to work out the atomic structure of a sample based on the diffraction pattern it produced when exposed to X-rays.

 

The discovery was revolutionary, for the science of crystallography had been born. Bragg’s Law made it possible for scientists to see the world on an entirely different scale. For the first time, they could effectively pinpoint the particles inside their samples. The twentieth century saw scientists solve countless structures in this way, and these discoveries have led to the development of modern medicine, engineering and technology. By the end of the century, scientists knew more about the world around us than was ever thought possible.

 

The Bragg’s carried out their early experiments with the first spectrometer, a small machine capable of producing basic X-rays. But this process was laborious and fraught with difficulty. These days, scientists have access to synchrotrons like Diamond, capable of producing intense light, 10 billion times brighter than the sun. This high-quality light is something the Braggs could only have dreamed of, and it means that scientists can now visualise particles a trillion times smaller than a pinhead.

 

Modern scientists also have robots capable of quickly testing many samples, and advanced detectors which are so powerful that they can image individual atoms and molecules. This pioneering technology means that what once took scientists years can now be done in minutes. If Dorothy Hodgkin had had access to Diamond when she was researching insulin, what took her 34 years could have been completed in a single hour. Thanks to advances in technology, what was once near impossible has now become routine.

These days, crystals truly are a scientist’s best friend. Because of new technology, contemporary scientists have the ability to not just examine but actually manipulate and change the atomic structure of materials. This has led to great advances in new materials and drug design.

 

Crystallography experiments at Diamond have recently yielded a potential vaccine for foot-and-mouth disease and have helped scientists to study T-Cells: a natural defence mechanism in the body which could provide an effective treatment against cancer. These are just two examples of modern crystallography in action; the technique is vital in fields as diverse as renewable energy, modern architecture, nanotechnology, cultural conservation, planetary research and health and medicine. Behind the scenes, crystallography is at the heart of modern science.

Crystallography has made many people’s lives better in profound and myriad ways, and it will continue to do so for as long as there are scientists to use it. In the future, if we arrive at a cure for HIV and cancer, or if we develop ways of living on Mars, or creating a world free from fossil fuels, crystallography will undoubtedly have a role to play.

 

Quietly serving millions of people around the world, this technique has come a long way from the days of the Braggs, but the concept of pairing crystals with X-rays to reveal the hidden nature of our world remains the same. So here’s to crystallography, science’s quiet star. Forever may it shine.