RE: high B-factors for some ncs copies

[Phil Jeffrey <phil@xray2.mskcc.org>]

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On Fri, 25 Jun 1999, Brent Segelke wrote:

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> As a counter point to Phil's remarks, I've taken a structure from the
> database and rerefined it with tight NCS and been able to achieve the same
> Rvalue, better geometry, lower RMSD between models, and lower RMSD of B.

You know, after all these years in xtallography I'm tempted just to point
out that for anything anyone says, there must be at least 1 counter
example, and often more like 10 of them.

There is no gospel in protein crystallography, only careful observation.

> This was a case in which one monomer of a trimmer had a much higher average
> B than the other two monomers.  'course this wasn't the case when I applied
> strong NCS restraints on B.

I'll stand by my initial observation about Cdk2:CyclinA.  See above re:
counter examples.


Phil  (speaking as someone who's moderately committed to NCS)
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| Phil Jeffrey                                  |                             |
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