Fluorescence Tools

Fluorescence Tools provides FRET-assisted structural modeling by integrating Förster Resonance Energy Transfer (FRET) experimental data with simulations to derive state-specific biomolecular structures.

Key Features:

• Automated experimental design: Optimizes the number and specific pairs of fluorophores for FRET experiments to minimize uncertainty and maximize integrative-model accuracy.
• FRET-assisted coarse-grained structural modeling: Constructs coarse-grained biomolecular models constrained by FRET distance data.
• All-atom molecular dynamics refinement: Refines coarse-grained models using all-atom molecular dynamics (MD) simulations to improve structural resolution.
• Quantitative quality estimate: Provides quantitative accuracy metrics, including RMSD comparisons of Cα atoms to X-ray structures, emphasizing accuracy over precision.

Scientific Applications:

• State-specific structure determination: Derives state-specific structures of complex and dynamic biomolecular assemblies from sparse FRET data combined with simulations.
• Experimental design guidance: Identifies optimal sets of FRET pairs (e.g., 15–23 pairs) to reduce uncertainty and enable accurate structural models.
• Benchmarking and validation: Applied to proteins with multiple conformational states and benchmarked to achieve approximately 3 Å Cα RMSD versus X-ray structures using 15–23 FRET pairs.

Methodology:

Integrates experimental FRET data with computer simulations, performs automated selection of fluorophore pairs, builds coarse-grained models constrained by FRET distances, refines models with all-atom MD simulations, and assesses quality via RMSD-based comparisons to X-ray structures.