With the goal to facilitate the global multi-method analysis (GMMA) of biophysical protein interactions data, we have further expanded the software SEDPHAT with new simulation and analysis models. This platform offers a seamless combination of data types from different techniques, with a variety of interaction models, and specific statistical functions for the analysis of multi-component interactions in a multi-method approach. Specifically, in the reporting period we have expanded the capabilities of the software for isothermal titration calorimetry (ITC). We have shown that the classical c-value criterion for useful sample concentrations in ITC becomes meaningless in the context of multi-site and multi-component interactions. Therefore, we have developed a new experimental planning tool that is based on the visualization of differential enthalpy isotherms. Two-dimensional or three-dimensional depictions of these enthalpy changes with sample concentration in two or three components, respectively, allow the user to identify promising experimental conditions and simulate ITC data. These may be combined in a global analysis to explore whether experiments will likely generate information to determine thermodynamic binding parameters. We believe this will be very helpful in the study of multi-protein and multi-site interactions by ITC. In order to disseminate this tool and facilitate its application by colleagues, we have held multiple workshops at NIH in Bethesda, which have generated positive feedback and software improvements. This was accompanied by the release of a modified version of our SEDPHAT software, called ITCsy, that streamlines applications to ITC.

Project Start
Project End
Budget Start
Budget End
Support Year
9
Fiscal Year
2015
Total Cost
Indirect Cost
Name
Biomedical Imaging & Bioengineering
Department
Type
DUNS #
City
State
Country
Zip Code
Zhao, Huaying; Boyd, Lisa F; Schuck, Peter (2017) Measuring Protein Interactions by Optical Biosensors. Curr Protoc Protein Sci 88:20.2.1-20.2.25
Brautigam, Chad A; Zhao, Huaying; Vargas, Carolyn et al. (2016) Integration and global analysis of isothermal titration calorimetry data for studying macromolecular interactions. Nat Protoc 11:882-94
Chaires, Jonathan B; Hansen, Lee D; Keller, Sandro et al. (2015) Biocalorimetry. Methods 76:1-2
Zhao, Huaying; Piszczek, Grzegorz; Schuck, Peter (2015) SEDPHAT--a platform for global ITC analysis and global multi-method analysis of molecular interactions. Methods 76:137-148
Zhao, Huaying; Schuck, Peter (2015) Combining biophysical methods for the analysis of protein complex stoichiometry and affinity in SEDPHAT. Acta Crystallogr D Biol Crystallogr 71:3-14
Gustchina, Elena; Li, Mi; Ghirlando, Rodolfo et al. (2013) Complexes of neutralizing and non-neutralizing affinity matured Fabs with a mimetic of the internal trimeric coiled-coil of HIV-1 gp41. PLoS One 8:e78187
Keller, Sandro; Vargas, Carolyn; Zhao, Huaying et al. (2012) High-precision isothermal titration calorimetry with automated peak-shape analysis. Anal Chem 84:5066-73
Coussens, Nathan P; Schuck, Peter; Zhao, Huaying (2012) Strategies for assessing proton linkage to bimolecular interactions by global analysis of isothermal titration calorimetry data. J Chem Thermodyn 52:95-107
Zhao, Huaying; Schuck, Peter (2012) Global multi-method analysis of affinities and cooperativity in complex systems of macromolecular interactions. Anal Chem 84:9513-9
Gondeau, Claire; Corradin, Giampietro; Heitz, Frédéric et al. (2009) The C-terminal domain of Plasmodium falciparum merozoite surface protein 3 self-assembles into alpha-helical coiled coil tetramer. Mol Biochem Parasitol 165:153-61