PSI recorded a sodium pump in action for the first time using a new radiation technology

Researchers at the Paul Scherrer Institute (PSI) have recorded for the first time, in action, a light-driven sodium pump from bacterial cells.

It has been possible thanks to the new X-ray free-electron laser SwissFEL, used by PSI researchers for their investigations.

They used a technique called serial femtosecond crystallography. A femtosecond is one-quadrillionth of a second; a millisecond is the thousandth part.

The sample to be examined – in this case a crystallised sodium pump – is struck first by a laser and then by an X-ray beam.

In the case of bacterial rhodopsin, the laser activates the retinal, and the subsequent X-ray beam provides data on structural changes within the entire protein molecule.

Since SwissFEL produces 100 of these femtosecond X-ray pulses per second, recordings can be made with high temporal resolution.

The results promise progress in the development of new methods in neurobiology.

Read more in the Paul Scherrer Institute’s Press Release.