PMID- 8951649 OWN - NLM STAT- MEDLINE DCOM- 19970328 LR - 20191101 IS - 0920-654X (Print) IS - 0920-654X (Linking) VI - 10 IP - 5 DP - 1996 Oct TI - Computational combinatorial ligand design: application to human alpha-thrombin. PG - 372-96 AB - A new method is presented for computer-aided ligand design by combinatorial selection of fragments that bind favorably to a macromolecular target of known three-dimensional structure. Firstly, the multiple-copy simultaneous-search procedure (MCSS) is used to exhaustively search for optimal positions and orientations of functional groups on the surface of the macromolecule (enzyme or receptor fragment). The MCSS minima are then sorted according to an approximated binding free energy, whose solvation component is expressed as a sum of separate electrostatic and nonpolar contributions. The electrostatic solvation energy is calculated by the numerical solution of the linearized Poisson-Boltzmann equation, while the nonpolar contribution to the binding free energy is assumed to be proportional to the loss in solvent-accessible surface area. The program developed for computational combinatorial ligand design (CCLD) allows the fast and automatic generation of a multitude of highly diverse compounds, by connecting in a combinatorial fashion the functional groups in their minimized positions. The fragments are linked as two atoms may be either fused, or connected by a covalent bond or a small linker unit. To avoid the combinatorial explosion problem, pruning of the growing ligand is performed according to the average value of the approximated binding free energy of its fragments. The method is illustrated here by constructing candidate ligands for the active site of human alpha-thrombin. The MCSS minima with favorable binding free energy reproduce the interaction patterns of known inhibitors. Starting from these fragments, CCLD generates a set of compounds that are closely related to high-affinity thrombin inhibitors. In addition, putative ligands with novel binding motifs are suggested. Probable implications of the MCSS-CCLD approach for the evolving scenario of drug discovery are discussed. FAU - Caflisch, A AU - Caflisch A AD - Department of Biochemistry, University of Zurich, Switzerland. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't PL - Netherlands TA - J Comput Aided Mol Des JT - Journal of computer-aided molecular design JID - 8710425 RN - 0 (Enzyme Inhibitors) RN - 0 (Ligands) RN - 0 (Macromolecular Substances) RN - 0 (Pyrrolidines) RN - 5L0H5Q9VAG (Methylguanidine) RN - EC 3.4.21.5 (Thrombin) SB - IM MH - Binding Sites MH - *Computer-Aided Design MH - *Drug Design MH - Enzyme Inhibitors/chemistry MH - Humans MH - Ligands MH - Macromolecular Substances MH - Methylguanidine/chemistry MH - Models, Molecular MH - Molecular Structure MH - Protein Conformation MH - Pyrrolidines/chemistry MH - Software MH - Static Electricity MH - Thermodynamics MH - Thrombin/antagonists & inhibitors/*chemistry EDAT- 1996/10/01 00:00 MHDA- 1996/10/01 00:01 CRDT- 1996/10/01 00:00 PHST- 1996/10/01 00:00 [pubmed] PHST- 1996/10/01 00:01 [medline] PHST- 1996/10/01 00:00 [entrez] AID - 10.1007/BF00124471 [doi] PST - ppublish SO - J Comput Aided Mol Des. 1996 Oct;10(5):372-96. doi: 10.1007/BF00124471.