[ccp4bb] interactive program to mutate RNA models

[Green, Todd]

Hello all,
I have models of poly-U RNA that I would like to mutate to other bases. Is 
there a program that I can use to mutate the base say similar to the way COOT 
mutates the side-chains of amino acids? It would be a plus if I could mutate 
the base only, ie. fixing the ribose-phosphate backbone. Thanks in advance for 
suggestions.
Best-
Todd Green
University of Alabama at Birmingham