iMODS

iMODS performs Normal Mode Analysis (NMA) in internal (dihedral) coordinates to analyze collective motions of proteins and nucleic acids.

Key Features:

• Internal Coordinate Formulation: Employs internal (dihedral) coordinates for NMA to preserve stereochemistry and efficiently model large macromolecular structures.
• Transition Pathways Generation: Generates feasible transition pathways between two homologous structures to characterize conformational changes.
• Resolution Flexibility: Supports customizable model resolution via coarse-grained atomic representations and elastic network potentials.
• Vibrational Analysis and Motion Representations: Performs vibrational analysis and produces morphing trajectories, motion animations, and an affine-model-based arrow representation for domain dynamics across resolution scales.
• Integration with Advanced Modeling: Produces all-heavy-atom conformations that can be integrated into more advanced modeling or sampling strategies.

Scientific Applications:

• Structural biology: Probes collective motions of proteins and nucleic acids to elucidate conformational dynamics.
• Protein function elucidation: Assists in identifying motion modes that underlie protein function and domain movements.
• Nucleic acid interaction analysis: Characterizes conformational behavior relevant to nucleic acid interactions.
• Drug design: Informs drug design by revealing conformational changes and collective motions relevant to target states.
• Enzyme mechanism studies: Supports enzyme mechanism studies by modeling large-scale motions involved in catalysis.
• Molecular recognition: Aids understanding of molecular recognition processes by analyzing potential conformational changes and collective motions.

Methodology:

Applies Normal Mode Analysis (NMA) using internal (dihedral) coordinates, employs coarse-grained atomic representations and elastic network potentials, generates transition pathways between homologous structures, and reconstructs all-heavy-atom conformations and affine-model-based motion representations.