UCSF Chimera is a program for the interactive visualization and analysis of molecular structures and related data, including density maps, trajectories, and sequence alignments. High-quality images and animations can be generated. Chimera includes complete documentation and is free of charge for academic, government, nonprofit, and personal use. Chimera development was supported by the National Institutes of Health (P41-GM103311).

UCSF ChimeraX is the next-generation molecular visualization program from the RBVI, following UCSF Chimera. We encourage Chimera users to try ChimeraX for much better performance with large structures, as well as other major advantages. ChimeraX replaces a significant subset of Chimera features, includes several completely new features, and is under active development. Users may certainly choose to use both programs, and it is fine to have both installed.

Feature Highlight

Nucleotides

Special representations of DNA and RNA can be displayed with the Nucleotides tool or the command nucleotides. Different levels of abstraction are available. The figure shows a ribbon backbone combined with the following sidechain (sugar/base) options:

• ladder rungs
• filled-ring atomic representations
• "lollipops" in which bases are shown as ellipsoids and sugars as tubes

Bases can also be displayed as boxes or elliptical tubes, with or without bumps to indicate orientation. The colors of the special representations will update automatically to match the corresponding atoms.

(More features...)

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Gallery Sample

Peroxiredoxin Wreath

Peroxiredoxins are enzymes that help cells cope with stressors such as high levels of reactive oxygen species. The image shows a decameric peroxiredoxin from human red blood cells (Protein Data Bank entry 1qmv), styled as a holiday wreath.

See also the RBVI holiday card gallery.

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