How to Check a Molecular Docking Pose Beyond the Vina Score: PoseBusters, PLIFs, and Interaction Recovery

A docking result contains several different kinds of evidence that are often compressed into a single ranking. Vina reports an approximate affinity for each generated mode and RMSD values relative to the first reported mode—not automatically relative to a crystallographic ligand [1]. A more negative score can help order poses produced under one frozen protocol, but it does not certify that the molecule was prepared correctly, that the pose is physically credible, or that the compound will bind.

The useful question is therefore not “Is this score good?” but “Which independent checks does this pose survive, and which uncertainty still governs the decision?” The five-layer audit below creates that record before a pose enters prioritization, molecular dynamics, synthesis, or experimental testing.

Keep the layers separate. A correct ligand in the correct pocket may still contain a severe clash. A clash-free pose may miss a catalytic or conserved interaction. A pose that reproduces a known interaction may still arise from an unvalidated protocol. Recording a pass or failure at each layer makes disagreement visible instead of hiding it inside one composite impression.

Before review, freeze the receptor file, ligand state, search box, scoring function, exhaustiveness, seed policy, pose count, energy range, and software version. Otherwise a pose comparison can silently become a comparison of different protocols.

If a crystallographic reference exists, align receptors with a justified atom selection and calculate ligand-to-reference RMSD separately. Preserve the mapping and symmetry treatment. Even a low crystallographic RMSD is not enough: the PoseBusters study showed that poses can be geometrically close while failing chemical or physical validity checks [2]. Conversely, a novel ligand without a matching crystal pose cannot be judged by reference RMSD, so pocket, physicality, interactions, controls, and uncertainty become more important.

PoseBusters packages a set of automated checks for molecular consistency and physical plausibility [2]. Treat its output as a diagnostic panel: a failed check identifies a reason to reject or investigate; passing the panel means that those encoded problems were not detected. It does not turn a docked pose into an experimentally verified complex, and results still depend on the supplied receptor and ligand chemistry.

Repeat stochastic docking with recorded seeds or a declared seed policy. Consistent recovery across runs can reveal sampling stability, while disagreement exposes an unresolved search or scoring problem. It still does not prove the shared pose is correct. For library decisions, move from pose triage to a target-specific validation plan that defines controls, failure handling, discrimination metrics, and acceptance criteria before screening.

The existing guide to Vina affinity, RMSD, and pose selection explains the engine output. This article begins at the next decision: whether a selected pose survives independent structural and interaction checks. The distinction matters because a polished visualization can make several unresolved assumptions look like one coherent result.

MolNexus 0.1.1 provides a local Windows 10/11 64-bit workflow around AutoDock Vina 1.2.7. It connects supported receptor and ligand inputs, preparation review, search-box and run settings, Vina or Vinardo scoring, Mol* pose inspection, result tables, CSV and structure exports, ZIP export, and local SQLite history. These capabilities help preserve the run and inspect candidate poses.

MolNexus does not run PoseBusters or ProLIF, calculate a PLIF validation score, choose the biological target or receptor state, or certify scientific validity. Use its exported structures with separately versioned quality-control tools when those checks are required. The free trial includes two ligand docking runs; that is enough to test workflow fit, not predictive performance.