[ccp4bb]: unknown ligand

[Phil Evans <pre@mrc-lmb.cam.ac.uk>]

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Peer Mittl writes:
 > 
 > Does anybody know of a systematic method to assign additional electron
 > density in a binding site to a possible (but so far unknown) ligand
 > molecule, or is there only the empirical "it looks like as ..."-method. In
 > principle it should be feasible to place solvent molecules into the
 > spurious electron density and use this "solvent-molecule" to search a small
 > molecule databank. Unfortunately I donīt know of any databank that allows
 > such an approach.
 > 

This is a well-established method

Hamlet: Do you see yonder cloud that's almost in shape of a camel?
Polonius: By the mass, and 'tis like a camel, indeed.
Hamlet: Methinks it is like a weasel.
Polonius: It is backed like a weasel. 
Hamlet: Or like a whale? 
Polonius: Very like a whale.

William Shakespeare (1564 - 1616), "Hamlet", Act 3 scene 2