Hi,
Barring orientation mishaps - it almost sounds like you have an ethyl
rather than a methyl ester...
Could it be that your compound is an ester of ethanol rather than methanol?
Artem
> Dear ccp4 experts,
> I am trying to solve the structure of one esterase with its substrate. The
> structure was solved by MR to the resolution 2.2 A. In the active site, I
> can see clearly the different density map of the substrate (S- methyl
> hydroxy isobutyrate). After puting the substrate into that density map, I
> use Refmac to run restrain refinement at 0.1 weighting term.
> Even though the substrate fits to the different map very well, a big
> different map appears at one end of the substrate after Refmac refinement.
> I
> attach the image so that it's easy to see the problem.
> I tried to put water or Na (because the crystallization contains: 1M
> sodium
> citrate, 100mM Na Cacodylate, 20% glycerol) but it didn't work.
> I tried to use CNS instead of Refmac, however the result is worse since
> the
> R-free is increased and the different map is still there. Because I am new
> with CNS so I don't know which parameters I should adjust.
> Do you have any suggestion to solve this problem? Thank you very much for
> all of your helpful advice!
>
> My best regards,
> TriNgo,
> PhD student,
> Sungkyunkwan University, Korea
>
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