It is out of principle misleading to think of the Matthews coefficient as one hard number. Xinghua mentions it actually: 'with 87 % confidence' (although 'confidence as in confidence interval' is a statistically too hard term here imho). The Matthews probability calculator gives a more complete picture of the probable values and their distribution.
http://www.ruppweb.org/mattprob/default.html
BR
-----Original Message-----
From: CCP4 bulletin board [mailto:[log in to unmask]] On Behalf Of Christian Biertuempfel
Sent: Friday, June 25, 2010 9:34 AM
To: [log in to unmask]
Subject: Re: [ccp4bb] Matthews coefficient
Dear Xinghua,
Of course, you can have 2 molecules in the asu. However, if things don't
it is worth to double-check your space group or check for twinning.
Cheers
christian
xinghua qin wrote:
> hi CCPeers
> The Matthews coefficient of my protein is 3 calculated with
> matthews-cell content analysis CCP4 programe with 87% confidence , but
> when doing the refinement the third molecular couldn't get into the unit
> cell because of too many clashes.Deletion of the clashed AA did not
> work well, Then I used two molecules in the unit cell, After refining
> with Refmac, I found that the R factor is 0.29, R free is 0.40.I believe
> the value can be better with the real space refinement.But the question
> is that can the calculated Matthews coefficient be wrong?
>
> Best regards
>
> Xinghua Qin
>
> --
> Xinghua Qin
> College of Biological Sciences
> No.2, Yuan Ming Yuan West Road
> Haidian District,Beijing,China,100094
> Tel: +86-10-62732672
--
_______________________________________________________________________
Dr. Christian Biert�mpfel
Laboratory of Molecular Biology
NIDDK/National Institutes of Health phone: +1 301 402 4647
9000 Rockville Pike, Bldg. 5, Rm. B1-03 fax: +1 301 496 0201
Bethesda, MD 20892-0580
USA
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