In Situ Measurements of Polypeptide Samples by Dynamic Light Scattering: Membrane Proteins, a Case Study.

Integral membrane proteins are important drug targets that are critical in supporting many biological processes. Despite that, the study of their structure-function relationships remains a major goal in structural biology, yet progress has been hampered by inherent challenges in the production for stable and homogeneous protein samples. Dynamic light scattering provides a straightforward probe of protein quality in solution, particularly in relation to stability and aggregation. However, the necessity to use large amounts of sample and the low-throughput nature of the analysis remain as major bottlenecks of the technique.Here, we present a protocol for dynamic light scattering measurements that are executed in a fully automated fashion for low-volume samples, in situ. The protocol offers a generic pre-screening method for downstream structural studies of biomolecules using higher-resolution approaches such as X-ray crystallography, electron microscopy, small-angle X-ray scattering, and NMR .