Pro4S Regression

Pro4S Regression predicts quantitative protein solubility (0–1 score) from amino acid sequence plus 3D structure provided as PDB or CIF, using fused sequence, structural, and surface features. The API supports batches of up to 4 sequences (≤2048 residues) with single-chain structures and returns a continuous solubility_score suitable for ranking and filtering. Typical uses include prioritizing highly expressible, soluble designs and excluding unstable or aggregation-prone candidates in protein engineering workflows.