Automated protein conformation studies

An automated system for taking circular dichroism measurements of protein conformation has been developed by European scientists, freeing operator time and accelerating analysis. CD is a classical method for following conformational changes in biomolecules, including peptides and proteins, but is a time-consuming procedure due to demands on the optical properties of the sample cells and the high standard of cell cleaning required.

These limitations have now been addressed by Sandro Keller and Sebastian Fiedler from the University of Kaiserslautern, Germany and Lindsay Cole from Applied Photophysics Ltd., Leatherhead, UK, as they discuss in Analytical Chemistry. They devised a fully automated sample handling system for protein conformation studies by CD spectroscopy, based on the transfer of samples from four 96-well plates to the flow-through sample cell. The liquid handling robot also took care of cell cleaning, which eats up more than 75% of the time.

The system was demonstrated by the unfolding of hen egg white lysozyme induced by denaturing with guanidinium chloride which gave measurements of high precision and good reproducibility. The good performance was attributed to a fall in the number of variable operations, because the flow-through cell is held in the same position and it is filled, emptied and cleaned in a standardised automated manner.