*** For details on how to be removed from this list visit the *** *** CCP4 home page http://www.ccp4.ac.uk ***
Sorry, one correction to what I just posted. I have seen three cases where the correct space group is C2 rather than R32. Sometimes, at low resolution, you WILL get a solution in R32, but the three molecules are related by non-crystallographic three-fold symmetry in C2. Thus, there is one unique axis, the monoclinic b-axis, but three nearly-equivalent 2-folds in R32. So yes, you should try to search in C2, but you will have three choices of the correct b-axis if you originally indexed in R32 since all three will look metrically equivalent. Bernie On Thu, January 4, 2007 10:21 pm, Jenny wrote: > *** For details on how to be removed from this list visit the *** > *** CCP4 home page http://www.ccp4.ac.uk *** > > > Hi, All > > I got a set of data of my crystal recently(2.3 A) and tried to do MR > because it's only several residues different from the wild type. The > problem is that after we indexed with HK:2000, it shows the primitive > rhombohedral space group, with the cell size > 137.200 137.200 86.682 90.000 90.000 120.000. > > The protein is only 90 residues ( 10kDa), so looks to me the cell size > is a little big.But anyway, we tried to use the wt structure and do > MR, didn't find the solution for the space group R32.We also tried C > centered monoclinic space group and primitive triclinic space group, > didn't get any luck either.Since the crystal is grown from the > preticipate, so I started to worry that maybe the crystal isn't my > protein.After I checked with SDS gel of the crystal, it shows very > similar MW as the target protein.Now I'm waiting for the sequencing > result. > > I heard that it's quite tricky for R32 and I wondered what's that.If > the sequence comes back to be correct, what should I do the next > step?If MR doesn't succeed, does this mean, the new mutant protein is > very different from the wild type? > > Any suggestions would be appreciated. > > Thanks. > > Jenny >
