4.5.4 MODIFY — Changes the Attributes of an Atom

4.5.4.1 Syntax

     MODIfy          (A4)    Fixed format
     
     NCHANG  (I5)
     
     NREST,ATOMT,ICODE,ANAME,CHARG  (I5,1X,A4,I5,1X,A4,F10.3)
        repeated NCHANG times

4.5.5 Function

NCHANG is the number of atoms to be modified. A card with the changed values must be read in for each atom to be changed (in any order). NREST and ATOMT are the residue number and atom type of the atom to be changed. ICODE, ANAME and CHARG are the new chemical type code (IAC array entry), new atom type and new atomic charge given to the atom. If a field is left blank, the old value is retained. Editing of this type could be used, for example, to change the carbonyl oxygen of a terminal residue to an atom with attributes corresponding to a carboxyl oxygen (in the standard execution of the program, modifications like this are done automatically if the proper type is specified with the sequence).