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<p class="MsoNormal">Hi everyone, </p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I had 2 questions regarding occupancy and maps generated in ligand-bound regions for various ligand models potentially present in the structure:</p>
<p class="MsoNormal"><o:p> </o:p></p>
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<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo2">I�ve been working with some 2.0 angstrom structures and trying out refinements with 2 sets of bound ligands at varying occupancies (at the same active site) to get an approximate idea
of their relative populations in the structure. For one set of ligands, I observe 2Fo-Fc density in regions uniquely occupied by them even when their occupancy is zero. Could there be a reason why this is the case?</li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo2">Additionally, I observe red Fo-Fc density in the same region when the occupancy is set to 1.0. It disappears at lower occupancies of 0.7 indicating that a lower population of this
ligand is present. However, when the occupancy is very low, we don�t see an equivalent green Fo-Fc density popping up in the same region. Could there be a reason for why the red Fo-Fc density at high occupancy doesn�t translate to green Fo-Fc for the same
region at low occupancy?</li></ol>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any information or resources that could give me more insight into this question would be really helpful!</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,</p>
<p class="MsoNormal">Vatsal </p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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