Dear Dale Tronrud, Thanks for your advise. Initially, i focused on the shape of the density. As you suggest, i checked all possible biological molecules and common additives used in purification and crystallization. I found that the structure of bis-tris-propane is similar to the target density. And the environment of crystallization contain this molecular. So, i will try it. Thanks again! Wei
At 2013-07-18 02:20:10,"Dale Tronrud" <det...@uoxray.uoregon.edu> wrote: > > Do you have any reason to expect either of these molecules would be in >your crystal? The model you build has to fit the density, be consistent with >the surrounding environment (which you haven't shared with us) and you >have to have some story for how that molecule got in your crystal. Personally >I would steer away from industrial compounds and focus more on biological >molecules and common additives used in purification and crystallization. > > The environment is critical to identifying this molecule. What hydrogen > bonds >does this molecule make? What charges are near by? Certainly the presence >or absence of hydrogen bonds will distinguish between these two compounds >before you go to the trouble to build a model of either. > >Dale Tronrud > >On 7/17/2013 6:35 AM, Wei Feng wrote: >> Dear all, >> Thank you for your advices. >> I had tried to use MPD and pyrophosphate etc to fix the density map but all >> of them were too small. >> We guess that the molecular formula should be C8H18O2. So we search this >> formula in google and find two candidate molecules >> 1: http://flyingexport.en.ecplaza.net/dhad-99-5--137042-689140.html >> 2: http://en.m.wikipedia.org/wiki/Di-tert-butyl_peroxide >> Could you tell me how to get the coordinate of these molecules? >> Thank you for your time! >> Wei >> >> >> >> >
