These ebuilds come from http://dev.gentoo.org/~dberkholz/overlay/.
If you have some problems, go to the official site first.
cctbx : Computational Crystallography Toolbox ( http://cctbx.sourceforge.net/ )
mmtk : Molecular Modeling ToolKit for Python ( http://dirac.cnrs-orleans.fr/MMTK/ )
pgd-utils : Protein Geometry Database library and Python modules ( http://oregonstate.edu/dept/biochem/faculty/karplus.html )
pymmlib : Software toolkit and library of routines for the analysis and manipulation of macromolecular structural models ( http://pymmlib.sourceforge.net/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a zugaina
For Paludis use this rsync : rsync://gentoo.zugaina.org/zugaina-portage
If you have a problem : ycarus(-at-)zugaina.org