high B-factors for some ncs copies

[Susan Heffron <sheffron@uci.edu>]

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Hi all,

I am refining a structure with six molecules in the asymmetric unit. 
The data set is only to 2.8 A resolution.  I thought I was done with it,
having R-free at about 23% and R-work at about 18%.  But when I checked
average B-factors, here is what I saw:

Chain name     Atoms       Bave       Bsdv       Bmin       Bmax
     M1A        2894      33.57      18.77       2.00     100.00
     M1B        2894      42.50      19.15       2.00     100.00
     M2A        2894   ** 58.96 **   24.67       4.87     100.00
     M2B        2894   ** 56.48 **   25.61       2.00     100.00
     M3A        2894      34.52      21.01       2.00     100.00
     M3B        2894      40.98      21.16       2.00     100.00
     WAT          80      31.76      12.33       5.44      69.18

Two copies of my molecule have alarmingly high average B-factors. 

Refinement has been done primarily in X-plor, with one round of
refinement in CNS.  Strong ncs restraints have been used throughout.

How should I check whether these high B-factors indicate a problem with
chains m2a and m2b, or whether they simply have high B-factors?  Would
rigid-body refinement be appropriate?  Or annealed omit maps?  Or should
I remove the ncs restraints on those two copies?  I'd really like to
finish soon, and don't want to waste too much time...

                         Thanks in advance,
                         Susan
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        Susan Heffron
Dept. of Physiology and Biophysics                               
University of California, Irvine                
    Irvine, CA  92697                           
           U.S.A.
  phone:  (949) 824-4625
  FAX:    (949) 824-8540
  e-mail:  sheffron@uci.edu
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