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Optimization of protein samples for NMR using thermal shift assays.

ABSTRACT: Maintaining a stable fold for recombinant proteins is challenging, especially when working with highly purified and concentrated samples at temperatures >20 °C. Therefore, it is worthwhile to screen for different buffer components that can stabilize protein samples. Thermal shift assays or ThermoFluor(®) provide a high-throughput screening method to assess the thermal stability of a sample under several conditions simultaneously. Here, we describe a thermal shift assay that is designed to optimize conditions for nuclear magnetic resonance studies, which typically require stable samples at high concentration and ambient (or higher) temperature. We demonstrate that for two challenging proteins, the multicomponent screen helped to identify ingredients that increased protein stability, leading to clear improvements in the quality of the spectra. Thermal shift assays provide an economic and time-efficient method to find optimal conditions for NMR structural studies.

SUBMITTER: Kozak S

PROVIDER: S-EPMC4869703 | biostudies-other | 2016 Apr

REPOSITORIES: biostudies-other

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Optimization of protein samples for NMR using thermal shift assays.

Kozak Sandra S Lercher Lukas L Karanth Megha N MN Meijers Rob R Carlomagno Teresa T Boivin Stephane S

Journal of biomolecular NMR 20160317 4

Maintaining a stable fold for recombinant proteins is challenging, especially when working with highly purified and concentrated samples at temperatures >20 °C. Therefore, it is worthwhile to screen for different buffer components that can stabilize protein samples. Thermal shift assays or ThermoFluor(®) provide a high-throughput screening method to assess the thermal stability of a sample under several conditions simultaneously. Here, we describe a thermal shift assay that is designed to optimi ...[more]

PMID: 26984476

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