[Chimera-users] Feature suggestion - turn about pre-defined axis.

[Oliver Clarke]

Hi all,

Just have a minor feature suggestion that I think would make the command “turn” more useful in certain circumstances. Currently, one can use “turn” to rotate about the x,y or z axes; an arbitrary vector; or about a bond or pair of selected atoms (http://www.cgl.ucsf.edu/chimera/current/docs/UsersGuide/midas/turn.html).

Would it be possible for chimera to treat a predefined axis (e.g a helix axis, or the symmetry axis of an ion channel) as an atom-spec for the purposes of turn? As an example, “turn a1 45” would rotate 45 degrees about axis a1, with the default center of rotation corresponding to the midpoint of the axis. This would be very helpful for adjusting the relative orientations of symmetric oligomers, amongst other use cases.

Cheers,
Oliver.