The distance to your modelled water seems to be in agreement with an ionic interaction. What are the components of all buffers in the crystallisation components ?
Fred. ruheng wrote: > Dear all, > > Recently we are working on an archaebacteria protein which was > expressed and purified from /E.coli /by conventional procedures. After > we solved the structure, we found that there is an extra density in > one of the argninine as shown in the attached picture. It seems that > the density is larger than a methyl group and the atoms in the density > are not on one plane. So we are curious about whether the density is a > kind of posttranslational modification of arginine residues in the > protein, if it is, what kind of modification could it be? And most > important, what is the biological significance of this kind > modification? Any suggestions and dicussions are appreciated! > > Best, > Heng > <http://skydrive.live.com/redir.aspx?cid=2f5a8d98562e91e4&page=play&resid=2F5A8D98562E91E4%21199&type=1&Bpub=SDX.Photos&Bsrc=Photomail&parid=2F5A8D98562E91E4%21198&authkey=S1J8JneduIs%24> > > Strange density in arginine > <http://skydrive.live.com/redir.aspx?cid=2f5a8d98562e91e4&page=browse&resid=2F5A8D98562E91E4%21198&type=5&Bpub=SDX.Photos&Bsrc=Photomail&authkey=S1J8JneduIs%24> > > 查看幻灯片 > <http://skydrive.live.com/redir.aspx?cid=2f5a8d98562e91e4&page=play&resid=2F5A8D98562E91E4%21198&type=5&Bpub=SDX.Photos&Bsrc=Photomail&authkey=S1J8JneduIs%24> > 下载全部 > <http://skydrive.live.com/redir.aspx?cid=2f5a8d98562e91e4&page=downloadaszip&resid=2F5A8D98562E91E4%21198&type=6&Bpub=SDX.Photos&Bsrc=Photomail&authkey=S1J8JneduIs%24> > > 添加更多照片 > <http://skydrive.live.com/redir.aspx?cid=2f5a8d98562e91e4&page=upload&resid=2F5A8D98562E91E4%21198&type=5&Bpub=SDX.Photos&Bsrc=Photomail&authkey=S1J8JneduIs%24> > > > 此相册包含 1 张照片，并且将在 2011/10/02 之前在 SkyDrive 上提供。 > > 通过 Hotmail 共享您自己的幻灯片 <http://g.live.com/9wc9zh-cn/f_photos>
