Matching the water content in a solution to relative humidity in air
What is it about?
Protein crystals are usually 40 - 70% solvent and diffract X-rays weakly. Dehydrating protein crystals can decrease the solvent content and increase the quality of data that can be collected leading to a better model to understand the biology. In order to start dehydration the relative humidity that is equivalent to the liquid in which the crystal was grown must be found. Here we have provided a model to predict this.
Why is it important?
Protein crystallography is essential in the understanding of fundamental biological processes and drug design. Methods that can improve the resolution of the data collected are therefore important. This model predicts the starting point for experiments that can improve protein crystals and also finds that most vapour diffusion experiments (the standard proceedure to produce protein crystals) are in fact batch as the difference on relative humidity is negligable.