Discovering Life's Structure

Great 20th-century innovation
This scientific technique helps us see the atomic structure of the tiny molecules that make up almost everything around us. It has been so revolutionary that no fewer than 28 Nobel prizes have been awarded to projects related to crystallography.

It has enabled the discovery of crucial biological structures, from proteins to DNA, helping us understand, and potentially modify, their workings. The technique also helps scientists discover new drugs and fight viruses.

The x-ray crystallography process
1. The molecule is crystallized.

2. An X-ray beam is fired at the crystal.

3. The crystal splits the beam into many rays, diffracting them onto photographic film.

4. Scientists measure how the X-rays scatter and use complex mathematical equations to work out the molecular structure of the sample.
5. The structure is then visualized in a 3D model.

John Desmond Bernal was one of the pioneers of X-ray crystallography. He was a visionary scientist who saw that the technique could be applied to biology or, as he called it, the study of life itself.

He was the first to use crystallography to discover the structure of proteins.

Bernal worked at Birkbeck from 1937-1968 - as a professor of physics and later, crystallography.

He set up a new laboratory to work on protein structures and also made a notable contribution on the structure of liquids.

Bernal made sure Birkbeck's labs were fully equipped with everything necessary to carry out X-ray crystallography experiments.

Bernal said, 'The secret of life lies in the structure of proteins, and there is only one way of solving it and this is by crystallography.'

He made his own 3D models, such as this one, which demonstrates the 'perfect randomness' of water molecules.

Originally, it could take a year or more to determine a protein structure.

Bernal was the first to try to use computing to help with crystallographic calculations. The university's Computer Science department was born as an offshoot of Bernal’s Crystallography Department.

Bernal was an inspiring teacher and mentored crystallographers who went on to work on a huge range of molecules.

Among his students were Dorothy Crowfoot Hodgkin, who won the 1964 Nobel prize for solving the structure of vitamin B12, and Rosalind Franklin, who played a major part in the discovery of the DNA double helix - probably the most famous result of crystallography.

Rosalind Franklin did pioneering work on virus structure at Birkbeck, before her premature death in 1958.

This is her visualisation of the tobacco mosaic virus.

Bernal was one of the most influential scientists of his generation. He believed that science was central to society and a means of improving the condition of life.

He wrote extensively on the subject and campaigned for social responsibility among scientists and increased government support for scientific research.

He also made important contributions during World War II.

As government scientific advisor, he helped map the Normandy beaches, and designed an artificial mulberry harbour, used during the D-Day Landings.

The Social Function of Science, published in 1939, was his most celebrated work.

Bernal was a Marxist and a peace campaigner. Pablo Picasso came to England to attend a world peace conference in November 1950. At a dinner at Bernal’s flat above Birkbeck lab, Picasso made a mural of a man and a woman, signifying peace - the only mural Picasso ever made in England.

When Bernal’s flat was demolished to make way for a new college building, the mural was saved and is now part of the Wellcome Collection.

Under Bernal's leadership, Birkbeck’s Crystallography department became a world class centre of excellence.

X-ray crystallography is still the main technique for revealing the structure of almost anything.

Today's crystallographers do the same work as Bernal, but on a larger scale and with more sophisticated methods and machines.

Much of the process is now automated. Scientists have also developed new techniques to compliment X-ray crystallography, notably power diffraction and electron microscopy.

This 1980s X-ray machine had much more processing power.

Some work previously carried out through X-ray diffraction is now done using electron microscopy.

Scientists compare electron density maps to create 3D models...

...and visualise atomic structures with computer software.

Birkbeck has more modern X-ray machines these days.

Birkbeck staff recently solved the bacterial toxin that causes gas gangrene - a disease that can lead to amputations.

Discovering this toxin's structure is a vital step towards its prevention through medicine.