CalFitter

CalFitter performs global fitting and analysis of protein thermal denaturation data to characterize unfolding pathways and derive thermodynamic and kinetic parameters.

Key Features:

• Global fitting of diverse datasets: Simultaneous global fitting using any combination of input experimental data types to analyze unfolding behavior.
• Unfolding pathway models: A library of 12 mechanistic protein unfolding pathway models, including models that account for irreversible transitions.
• Parameter estimation and statistics: Estimation of optimal parameter values with confidence intervals and accompanying statistical information.
• SVD integration: Singular value decomposition (SVD) analysis for multi-wavelength spectral datasets integrated into the global fitting pipeline.
• Fitting of SVD components: Processed time- or temperature-evolved SVD components can be fitted alongside other experimental data types.
• Deconvoluted basis spectra: Derivation of deconvoluted basis spectra that serve as spectral fingerprints of macrostates populated during unfolding.
• Automated SVD analysis: Automated processing of SVD within the analysis workflow.

Scientific Applications:

• Protein folding pathway analysis: Quantitative description and comparison of mechanistic unfolding pathways using integrated experimental data.
• Thermostability engineering: Characterization of thermodynamic and kinetic parameters to support rational design of more stable proteins.
• Protein misfolding and aggregation studies: Analysis of unfolding and aggregation transitions to elucidate molecular bases of misfolding-related disorders.

Methodology:

Global nonlinear fitting of multiple experimental datasets to mechanistic unfolding models (12 models including irreversible transitions); parameter estimation with confidence intervals and statistical metrics; singular value decomposition (SVD) of multi-wavelength spectral datasets with fitting of time- or temperature-evolved SVD components and derivation of deconvoluted basis spectra.