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Questions and answers => MD simulations => Topic started by: piia600 on May 16, 2025, 05:50:16 am

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Title: Do I need gromacs to use dnaMD for simulations?
Post by: piia600 on May 16, 2025, 05:50:16 am

Hi all,

Thanks for the x3DNA-DSSR software which works wonderfully for single PDBs.

I have some MD simulations I would like to analyze with dnaMD. I ran them with Amber but converted them to GROMACS .xtc + .pdb files for analysis.

Do I need GROMACS version of dnaMD to analyze simulations or can I use the Python module of dnaMD without GROMACS for simulations?

PS. I am also lacking the link to download the 3DNA from the forum for some reason, my forum view is similar to unregistered users.

Title: Re: Do I need gromacs to use dnaMD for simulations?
Post by: xiangjun on May 16, 2025, 10:00:09 am

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Thanks for the x3DNA-DSSR software which works wonderfully for single PDBs.

Thanks for using DSSR and for posting your questions on the 3DNA Forum. As for the analysis of an ensemble, please see the DSSR manual  (http://docs.x3dna.org/dssr-manual.pdf), especially Section: "3.13 The --nmr option":

Quote from: DSSR Manual

The DSSR --nmr (or --md) option automates the analysis of an ensemble, such as NMR structures in the PDB or snapshots from MD simulations. The input coordinates file must be in either the classic PDB format where each model is delineated by MODEL/ENDMDL tags, or the mmCIF format where each ATOM/HETATM record has an associated model number.
...
The --json option makes it easy to parse the output of multiple models pragmatically. In addition to NMR structures, trajectories from MD simulations can also be processed. Popular MD packages (AMBER, GROMACS, CHARMM, etc.) all have their own specialized binary formats for trajectories. By design, DSSR does not work on these binary files. They must be converted to the standard PDB or mmCIF format to be analyzed by DSSR. The combination of --nmr and --json makes DSSR directly accessible to the MD community.

Quote

I have some MD simulations I would like to analyze with dnaMD. I ran them with Amber but converted them to GROMACS .xtc + .pdb files for analysis.

Do I need GROMACS version of dnaMD to analyze simulations or can I use the Python module of dnaMD without GROMACS for simulations?

I am not a practitioner of MD simulations. Questions related to dnaMD are best answered by its developer: hopefully @rkumar will chime in. See the thread Update of do_x3dna package (http://forum.x3dna.org/index.php?topic=1042.msg3765), which can be used with files generated by GROMACS.

Quote

PS. I am also lacking the link to download the 3DNA from the forum for some reason, my forum view is similar to unregistered users.

There have been too many spam registrations nowadays, so I must stay continuously vigilant to keep the Forum clean. You should now see the download link. Sorry for the inconvenience.

Best regards,

Xiang-Jun

Xiang-Jun

Funded by the NIH R24GM153869 grant on X3DNA-DSSR, an NIGMS National Resource for Structural Bioinformatics of Nucleic Acids

Created and maintained by Dr. Xiang-Jun Lu, Department of Biological Sciences, Columbia University