MST in METHODS – Challenging Samples Made Simple

An international team of scientists from NIH, University of Oxford, The Scripps Research Institute, University Nijmegen, MD Anderson Cancer Center, Weizmann Institute and LMU University published ground-breaking MST results in Methods. The results show that NanoTemper’s novel biophysical approach to determine affinities in solution allows measurements that were challenging before. The study includes, among others, GPCR, ion and small molecules binding events as well as dimerization measured in both buffered systems and in cell lysates. The data were obtained in free-solution with and without fluorescence labels on the Monolith NT.115 and NT.LabelFree devices offered by NanoTemper Technologies. “This publication is a very important one amongst the more than 70 MST publications that are available today since it shows the broad application range of MST and gives detailed instructions how to perform MST assays,” says Dr. Stefan Duhr, CEO of NanoTemper Technologies.

Abstract:
Microscale thermophoresis (MST) allows for quantitative analysis of protein interactions in free solution and with low sample consumption. The technique is based on thermophoresis, the directed motion of molecules in temperature gradients. Thermophoresis is highly sensitive to all types of binding-induced changes of molecular properties, be it in size, charge, hydration shell or conformation. In an all-optical approach, an infrared laser is used for local heating, and molecule mobility in the temperature gradient is analyzed via fluorescence. In standard MST one binding partner is fluorescently labeled. However, MST can also be performed label-free by exploiting intrinsic protein UV-fluorescence. Despite the high molecular weight ratio, the interaction of small molecules and peptides with proteins is readily accessible by MST. Furthermore, MST assays are highly adaptable to fit the diverse requirements of different biomolecules, such as membrane proteins to be stabilized in solution. The type of buffer and additives can be chosen freely. Measuring is even possible in complex bioliquids like cell lysate allowing close to in vivo conditions without sample purification. Binding modes that are quantifiable via MST include dimerization, cooperativity, and competition. Thus, its flexibility in assay design qualifies MST for analysis of biomolecular interactions in complex experimental settings, which we herein demonstrate by addressing typically challenging types of binding events from various fields of life science.