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<FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>I have a few questions related to a 3.5 angstrom structure. I have one helix that I am having trouble placing accurately. It does have a cysteine that disulfide bonds with the same residue in a symmetry related molecule. Can I restrain this distance during a rigid body refinement of the helix? How do I do this? What kind of parameters would be appropriate for the disulfide? <BR>
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My second question is whether someone can suggest appropriate distance_ideal, sigma, and slack for hydrogen bond restraints for a helix? Also, I have a 2 angstrom structure of this part of the complex for reference. <BR>
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Thanks!<BR>
Kendall Nettles</SPAN></FONT>
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