An ICM molecular object represents one or several molecules which can coexist in physical space, so that the energy of the molecular system can be calculated. For example, if you have two homologous molecules superimposed, multiple conformations of the same structure such as NMR structure determinations or alternative positions of a side chain, they must belong to different objects. The number of objects that may be loaded in ICM is limited only by the available computer memory. Objects may be of several types (see also: the
Type ( os_ 2 ) function):
"ICM"- the only complete type which is good for everything including energy calculations"X-Ray"- incomplete (stripped) object created by read pdb. The structure is determined by X-ray crystallography. Good for graphics and geometrical analysis"NMR"- incomplete (stripped) object, structure determined from NMR data, similar to the "X-ray" type above."Model"- incomplete (stripped) object, theoretical model also similar to the "X-ray" type above."Ca-trace"- incomplete (stripped) object, only alpha-carbon atoms."Simplified"- simplified representation.
ICM-molecular objects are created from residues and molecules described in the ICM
residue library.
Its content (sequences and names of molecules) is specified in an
ICM sequence file
(see also
IcmSequence
function). An ICM-object can also be created from a non-ICM object (e.g.
of X-Ray type) with the
convert
command.