Structures and their pocket measurements can be fetched directly from the Computed Atlas of Surface Topography of proteins (CASTp) database or read from local files previously returned by the CASTp server. In Chimera, the pockets are shown in a pocket list. Choosing rows in the list performs actions such as zooming in on pockets and selecting the surrounding atoms.

The figure shows the four largest pockets by volume identified by CASTp for PDB entry 1ovh (a cavity mutant of T4 lysozyme), shown in yellow, orange, pink, and magenta in order of decreasing volume. The largest is lysozyme's active site, with two openings. The second largest is the engineered cavity. Mutated positions are shown in red. Green balls are Cl^– ions.

Side-by-side views of a potassium channel structure (Protein Data Bank entry 1bl8) showing different approaches to cavity detection. On the left are molecular surface patches corresponding to the structure's two largest pockets by MS volume in the Computed Atlas of Surface Topography of proteins (CASTp) database. On the right is a tunnel in blue identified by the MolAxis server. Simple editing converted MolAxis output into a BILD file for display in Chimera. (More samples...)