At 21:38 GMT today, Europe’s Advanced Protein Crystallisation Facility (APCF) is scheduled to be launched to the International Space Station (ISS). Once on board the ISS – where it will stay for three months – it will perform a series of automated experiments that could be a step towards a better understanding of protein crystallisation.

Protein molecules are quite literally the substance of life. These vast arrays of atoms perform just about every important biochemical function inside living cells. They store and carry biological information; they act as catalysts in the hugely complex chemistry of life; and they provide membranes and cell walls.

Proteins are principally composed of amino acids, themselves made up of mainly carbon, hydrogen, oxygen and nitrogen. There are relatively few possible amino acids, but they can arrange themselves in an almost infinite number of ways, creating huge molecules that loop and fold into shapes of awesome complexity. The shape and structure of each protein is what gives it its special abilities.
If scientists can map that structure, they can learn more about the intimate workings of life. They will then be able to use their knowledge to synthesise proteins in the laboratory, which can lead to dramatically effective drugs. This is no easy task.

To analyse protein structure, scientists use a technique called X-ray crystallography – and for that to work, they need to have pure crystals of substantial size. But proteins do not crystallise easily and it is the large crystals that X-ray studies require that are especially hard to make. However, without the interfering tug of the Earth’s gravity, large crystals grow more easily – which is why the APCF will be heading for the International Space Station.

Even in the station’s microgravity environment, to grow protein crystals can be difficult. Previous experiments – performed both by ESA and NASA ñ have not always provided satisfactory explanations of the results obtained. But the APCF will use a new design of ‘reactor’ for crystal formation and a three-dimensional imaging system will allow scientists to make very precise observations of every stage of the process.

The August experiment will also run longer than most previous attempts; more than three months. When the crystal samples return to Earth in early December, researchers will be hoping for an early Christmas present.

Reference URL: