Isothermal titration calorimetry for characterization of recombinant proteins

• Published in: Current opinion in biotechnology 2019-02, Vol.55, p.9-15
• Main Authors: Baranauskiene, Lina, Kuo, Tai-Chih, Chen, Wen-Yih, Matulis, Daumantas
• Format: Article
• Language: English
• ISSN: 0958-1669; 1879-0429
• DOI: 10.1016/j.copbio.2018.06.003

[Display omitted] •ITC quantitatively determines the purity of recombinantly produced proteins.•Protein capability of binding a specific ligand is observed in a single experiment.•ITC is convenient for the determination of the intrinsic binding parameters. Isothermal titration calorimetry is widely used to measure the affinities and enthalpies of interaction between proteins and/or small molecules. The quantitative nature of the technique is especially useful in the characterization of recombinant proteins while determining the fraction of protein capable of binding a specific ligand and thus the protein purity. The revealed thermodynamic information sheds light on the binding mechanism, important for the targeted drug design of the biologics. Here we show examples how, together with the thermal shift assay, combination of both techniques enables characterization of protein stability and ligand binding. Furthermore, the binding-linked reactions that strongly affect the observed thermodynamic parameters and must be dissected to obtain the intrinsic parameters that are necessary for the structure-based rational drug design are being demonstrated using inhibitors of Hsp90, an anticancer target protein.