FASPR

FASPR performs fast and accurate protein side-chain packing and refinement to predict side-chain dihedral angles and improve protein structural models.

Key Features:

• Side-chain packing accuracy: Correctly predicts 69.1% of side-chain dihedral angles within 20° on native backbones, outperforming SCWRL4 (68.8%), CISRR (68.6%), RASP (67.8%), and SCATD (61.7%).
• Optimized scoring function: Uses a well-optimized scoring function to evaluate side-chain conformations.
• Deterministic searching algorithm: Employs a deterministic search strategy for side-chain placement.
• Algorithmic integration: Integrates dead-end elimination and tree decomposition techniques to enhance solution quality and efficiency.
• Computational speed: Demonstrated high throughput by packing 379 protein structures in 34.3 seconds, achieving the highest speed among tested methods.
• Robustness to backbone variation: Maintains or exceeds performance on non-native backbones, including I-TASSER-predicted and perturbed experimental structures.
• Benchmark comparisons: Explicitly compared against state-of-the-art PSCP programs CISRR, RASP, SCATD, and SCWRL4.

Scientific Applications:

• Protein structure modeling: Improves side-chain conformations in predicted and experimental protein structures to enhance model accuracy.
• Protein design: Provides accurate side-chain packing information useful for protein design and engineering studies.
• Structure–function analysis: Enables more precise analyses of protein structure–function relationships by refining side-chain placements.

Methodology:

Integrates dead-end elimination and tree decomposition with an optimized scoring function and a deterministic searching algorithm; evaluated on native and non-native backbones (including I-TASSER-predicted and perturbed experimental structures) using side-chain dihedral-angle accuracy within 20° and runtime benchmarks.