UCSF Chimera is a program for the interactive visualization and analysis of molecular structures and related data, including density maps, trajectories, and sequence alignments. It is available free of charge for noncommercial use. Commercial users, please see Chimera commercial licensing.

We encourage Chimera users to try ChimeraX for much better performance with large structures, as well as other major advantages and completely new features. ChimeraX includes a significant subset of Chimera features (with more to come, see the missing features list) and is under active development. Users may choose to use both programs, and it is fine to have both installed.

Chimera is no longer under active development, and is only updated for critical maintenance. Chimera development was supported by a grant from the National Institutes of Health (P41-GM103311) that ended in 2018.

Feature Highlight

Annotations from UniProt

The PDB/UniProt Info tool retrieves sequence and structure annotations for Protein Data Bank (PDB) entries using a Web service provided by the RCSB PDB. Sequences are displayed in Multalign Viewer, and feature annotations from UniProt are mapped onto the sequences as regions or colored boxes. In the region browser (figure at right):

• making a region Active selects any corresponding structure residues for further operations; only one region can be active at a time
• making a region Shown displays it in the sequence window
• the square color wells show (and allow changing) the region interior and border colors

UniProt annotations can also be fetched along with a sequence or mapped to a sequence already in Multalign Viewer regardless of whether the sequence is associated with a structure.

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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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