***  For details on how to be removed from this list visit the  ***
***          CCP4 home page http://www.ccp4.ac.uk         ***



I am refining several structures (all the same except point mutations,
2.0-2.8 A resolution) with Refmac5 (TLS+ISOT). One data set goes to 2.0
A and the refinement seems fine with 

REMARK   3   R VALUE            (WORKING SET) :  0.20075
REMARK   3   FREE R VALUE                     :  0.23986
REMARK   3   MEAN B VALUE      (OVERALL, A**2) :  12.944

First, I also noticed there were "problems making U positive....,'
during the refinement, actually, some of them were really big, say, -6. 

The low B also worries me, so I ran TLSANL, the total B of some residues
went negative. I then submitted the output pdb to PARVATI server, it
came back horrible, essentially listing all atom with "Non positive
definite ellipsoid" ..., the mean anisotropy is 0.15, all my other
structures have mean anisotropy of ~0.45 and normal average B about
40-50. 

I am not sure what I did wrong. Can anybody  advise how to generally
deal with this?

Thanks,



Tongqing

Reply via email to