Hello

We determined the structure of an enzyme-substrate complex. The substrate of the enzyme contains some partially occupied atoms. We were able to calculate the occupancies of these atoms using PHENIX_refine.

By the way, I would like to know the uncertainties of the occupancies of these atoms. How can I estimate the uncertainties? For example, the occupancy of an atom was calculated as 0.65; can we write it as 0.65 (+/- 0.05) or 0.65 (+/- 0.1)?  I know that it is related to B-factor and depends on the resolution (number of diffraction data per parameters), but I would like to know how to estimate (calculate?) the uncertainty.  Could someone tell me about this issue?

Best regards

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Masaki UNNO

Graduate School of Science and Engineering

Ibaraki University, JAPAN

4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan

Tel&Fax +81-294-38-5041

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