Hi Tim, an R-factor of 0.64 does not sound like a solution. You may try submitting your problem to our automated MR server CaspR and see if something pops up :
http://www.igs.cnrs-mrs.fr/Caspr2/ Kind regards, Karsten. On Monday 19 February 2007 17:15, [EMAIL PROTECTED] wrote: > I would take a well-ordered helix out of your > allegedly-correctly-placed model (BEFORE doing any refinement other > than rigid body), phase a 2Fo-Fc and an Fo-Fc map with it, and see if > the helix shows up. If it does, there is some reality in your > solution. If it doesn't, start over from scratch. > Actually, at your resolution a few fat side chains might do as a > reality check rather than an entire secondary structure element. In > fact, you might start by looking at lower-resolution maps, since you > almost certainly haven't phased the high-res terms properly. > Phoebe > > At 05:26 PM 2/18/2007, Tim Gruene wrote: > >Hi, > > > >I dare say with an R-factor of 0.64, your MR solution is simply wrong. > >Just into the blue, you could > >1) try various MR-programs (phaser, molrep, amore...) > >2) try a different search model > >3) try your best model but start with subdomains or chop off possibly > > flexible parts > >4) have a look at the CaspR server > > http://www.igs.cnrs-mrs.fr/Caspr2/index.cgi > >5) with crystals that give such good data try to get other pahse > > information (soaks, co-crystallisation, SAD (SAD at home), etc.) > >Good luck, Tim > > > >-- > >Tim Gruene > >Institut fuer anorganische Chemie > >Tammannstr. 4 > >D-37077 Goettingen > > > >GPG Key ID = A46BEE1A > > > >On Fri, 16 Feb 2007, Emmanuel Prata wrote: > >>Dear all, > >> > >>I have a data set of a protein soaked with sacarose, and the statistic > >>data is good until the molecular replacement (Rmerge 0,07 (24%), > >>I/Sigma 7 (2,7), completness (99,8 (98%)), and resolution 1,98A. After > >>this step, I can not get the Rfactor (64%) to drop (I believe the > >>spacegroup is correct). > >>Could anyone give me suggestions? > >>Thank you in advance, > >>Emmanuel Prata > > --------------------------------------------------------------------------- >------------------------------------------------ Phoebe A. Rice > Assoc. Prof., Dept. of Biochemistry & Molecular Biology > The University of Chicago > phone 773 834 1723 > fax 773 702 0439 > http://bmb.bsd.uchicago.edu/index.html > http://www.nasa.gov/mission_pages/cassini/multimedia/pia06064.html
