Superimposing crystal structures?

[Cornelius Krasel]

Hello netters,

I would like to superimpose different crystal structures in PDB format.
I know that there are programs who can do that, but I would like to do
it on a Linux box (e.g. to view the superimposed structures later
in Rasmol). I understand that I have to minimize the RMS between different
points (e.g. Calpha) but I am not sure _how_ to do this. I am especially
unsure if commonly used algorithms can account for the relative
orientation of a three-dimensional structure to another. (As you might
see, my mathematical background is virtually nonexistant :-)

Can anybody give me some hint (or even better, lead me to some piece of
C source code)?

Thanks in advance,

--Cornelius.

--
/* Cornelius Krasel, Abt. Lohse, Genzentrum, D-82152 Martinsried, Germany */
/* email: krasel at alf.biochem.mpg.de                 fax: +49 89 8578 3795 */
/* "People are DNA's way of making more DNA." (Edward O. Wilson, 1975)    */