Structure-Independent Genetic Algorithm-Based Molecular Optimization Using Pocket-Aware Molecular Representations
Year: 2026
Type: preprint
Abstract: De novo molecular design typically depends on target structures or ligand poses, limiting its applicability when structural information is unavailable. Here, we introduce the pocket-aware molecular representation-guided genetic algorithm (PAMR-GA), a target-structure-independent molecular optimization framework that learns pocket-aware representations from structure–activity relationship (SAR) data using only molecular structures represented as SMILES strings and experimental pIC50 values. By encoding latent spatial constraints inferred from SAR without requiring target structures, the learned representations guide genetic algorithm-based molecular optimization through a Gaussian process surrogate model. Benchmarking on BACE-1 demonstrated that PAMR-GA achieved comparable predictive performance, docking scores, and drug-likeness profiles to existing optimization approaches while generating molecules with substantially greater structural novelty and higher Murcko scaffold diversity. Evaluation on four additional targets, including a kinase, serine proteases, and an NADbinding enzyme, further showed consistent improvements in molecular novelty. These results highlight PAMR-GA as a complementary approach for incorporating SAR-derived spatial constraints into de novo molecular design without requiring target structures. 1 Scientific Contribution PAMR-GA enables structure-independent molecular design by learning binding constraints implicitly from 2D structure–activity relationship data, without requiring protein structures or ligand poses. By introducing a pocket-aware molecular representation that integrates solvent-accessible surface area and partial-charge features, PAMR-GA bridges molecular topology with 3D binding compatibility. Our results demonstrate that constrained generation, rather than improved activity prediction alone, drives structural novelty. Evaluation across five diverse targets from four protein classes highlights the generalizability of PAMR-GA as a broadly applicable framework for target-aware molecular design.
Source: ChemRxiv
Authors: Abhishek Kumar, Hyun Woo Kim
Language: English
Subfield: Drug Discovery
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7221636626