Problm with generation of all symmetry mates using xplor

[Yun-Xing Wang]

Dear Sir:
            I was trying to generate the second monomer of a homo-symmetric
    dimer from an x-ray crystallographic monomer deposited with a, b, c, alpha,
    betta and gamma unit cell constants.  The resulted dimer using your sample
    protocol on page 268-269 (with proper unit cell paramerters and rotation
    operation) is correct in terms of overall orientation that two monomers
    relate to each other, but with one little problem.  The some atoms of the
    residues on the very far tips of the two monomer structures are screwed up
    and their coordinates on Z-axis are not correct.  The Z-axis coordinates of
    these atoms on monomer I&II are exchanged.  In another words, for example,
    these atoms on monomer I have correct monomer I's x- and y-axis and monomer
    II's z-axis coordinates!  The interpretation of this is that these atomes
    are physically located outside of unit cell.  I am wondering if xplor
    program can handle this type of the problem within itself.
            I am looking foward to hearing from you soon on this matter.

            Regards

    yxw, Ph.D