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Updated: Feb 10, 2026

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
ANCA: Anharmonic Conformational Analysis of Biomolecular Simulations
Akash Parvatikar1, Gabriel S Vacaliuc2, Arvind Ramanathan2
1Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Abstract:
Anharmonicity in time-dependent conformational fluctuations is noted to be a key feature of functional dynamics of biomolecules. Although anharmonic events are rare, long-timescale (μs-ms and beyond) simulations facilitate probing of such events. We have previously developed quasi-anharmonic analysis to resolve higher-order spatial correlations and characterize anharmonicity in biomolecular simulations. In this article, we have extended this toolbox to resolve higher-order temporal correlations and built a scalable Python package called anharmonic conformational analysis (ANCA). ANCA has modules to: 1) measure anharmonicity in the form of higher-order statistics and its variation as a function of time, 2) output a storyboard representation of the simulations to identify key anharmonic conformational events, and 3) identify putative anharmonic conformational substates and visualization of transitions between these substates.
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