MDAnalysis — Molecular Dynamics Trajectory Analysis

Overview

MDAnalysis provides a uniform Python interface for reading and analyzing molecular dynamics trajectories regardless of MD engine (GROMACS, AMBER, NAMD, CHARMM, LAMMPS, OpenMM). It represents molecular systems as Universe objects containing an AtomGroup with positions, velocities, forces, and topology data. Trajectories are iterated frame-by-frame or analyzed in bulk using analysis modules for RMSD, RMSF, radius of gyration, hydrogen bonds, solvent-accessible surface area, and PCA. MDAnalysis integrates with NumPy, pandas, and matplotlib, making it the standard tool for post-simulation structural analysis in computational chemistry and drug discovery.

When to Use

• Computing RMSD and RMSF of protein backbone or specific residue groups after MD simulation
• Analyzing ligand binding stability: pocket RMSD, contact persistence, hydrogen bond occupancy
• Performing principal component analysis (PCA) on trajectory conformations
• Computing solvent-accessible surface area (SASA), radius of gyration, and end-to-end distance
• Extracting representative cluster structures from long MD trajectories for visualization
• Use GROMACS or AMBER analysis tools (gmx rms, cpptraj) instead for engine-specific analysis within a HPC pipeline
• Use OpenMM or GROMACS directly for running MD simulations; MDAnalysis is for post-simulation analysis

Prerequisites