FreeR flags from AutoBuild
Dear all May I enquire a simple question about AutoBuild - I input an experimental data (ccp4 mtz from Aimless) and a model from Phaser-MR to AutoBuild hoping that some mis-fit flexible regions could be re-build. May I know if the output mtz *overall_best_refine_data.mtz* contains the same FreeR flags as in the input, or would AutoBuild generate a new set of FreeR? Or in other words, are the R values directly comparable if I refine against the input experimental data mtz or the overall_best_refine_data.mtz? Thanks! Cheers Sam Tang Biochemistry Programme, School of Life Sciences, CUHK
Hi Sam,
I’m sure the PHENIX developers will clarify this point, but in any case you could just dump the two MTZ files to text ones:
mtzdump hklin file1.mtz > file1.txt
nref -1
end
mtzdump hklin file2.mtz > file2.txt
nref -1
end
and compare whether the same reflections are flagged in both.
HTH,
Luca
On 12 May 2016, at 04:59, Sam Tang
Hi,
Normally phenix.autobuild (I think phenix.refine is used in the refinement step of phenix.autobuild) will recognize the r_free_flag in the input data file (usually .mtz) whether in ccp4 convention or phenix convention. See document of autobuild, https://www.phenix-online.org/documentation/reference/autobuild.html#r-free-...
"In Phenix the parameter test_flag_value sets the value of the test set that is to be free. Normally Phenix sets up test sets with values of 0 and 1 with 1 as the free set. The CCP4 convention is values of 0 through 19 with 0 as the free set. Either of these is recognized by default in Phenix and you do not need to do anything special. If you have any other convention (for example values of 0 to 19 and test set is 1) then you can specify this with test_flag_value.
Note that phenix.refine and AutoBuild write out PDB files that contain the test_flag_value. AutoBuild can read this test_flag_value and use it automatically. However if there is a conflict between this test_flag_value and the default value based on your data file, you may have to specify which to use."
So I think the answer is YES.
Best!
Lu Zuokun
--
卢作焜
南开大学新生物站A202
Lu Zuokun, Ph.D. Candidate
College of Life Science, Nankai University
在 2016-05-12 16:01:09,"Luca Jovine"
Hi Sam,
Yes, autobuild will read the test set (freeR flags) and use these free R flags and write them out to overall_best_refine_data.mtz. So yes, the R-values are directly comparable if you refine against the input experimental data or overall_best_refine_data.mtz. As Luca mentioned, you could verify this with mtzdump or with:
phenix.mtz.dump -c original_data.mtz > original_data.txt
phenix.mtz.dump -c overall_best_refine_data.mtz > overall_best_refine_data.txt
?
All the best,
Tom T
________________________________
From: [email protected]
Hello Luca and Tom
Thanks for the clarification.
And yes I am now able to check the test set with mtzdump.
Thanks so much.
Kind regards
Sam Tang
Biochemistry Programme, School of Life Sciences, CUHK
On 12 May 2016 at 20:20, Terwilliger, Thomas Charles
Hi Sam,
Yes, autobuild will read the test set (freeR flags) and use these free R flags and write them out to overall_best_refine_data.mtz. So yes, the R-values are directly comparable if you refine against the input experimental data or overall_best_refine_data.mtz. As Luca mentioned, you could verify this with mtzdump or with:
phenix.mtz.dump -c original_data.mtz > original_data.txt
phenix.mtz.dump -c overall_best_refine_data.mtz > overall_best_refine_data.txt
All the best,
Tom T
------------------------------ *From:* [email protected] < [email protected]> on behalf of Sam Tang < [email protected]> *Sent:* Wednesday, May 11, 2016 8:59 PM *To:* PHENIX user mailing list *Subject:* [phenixbb] FreeR flags from AutoBuild
Dear all
May I enquire a simple question about AutoBuild - I input an experimental data (ccp4 mtz from Aimless) and a model from Phaser-MR to AutoBuild hoping that some mis-fit flexible regions could be re-build. May I know if the output mtz *overall_best_refine_data.mtz* contains the same FreeR flags as in the input, or would AutoBuild generate a new set of FreeR? Or in other words, are the R values directly comparable if I refine against the input experimental data mtz or the overall_best_refine_data.mtz?
Thanks!
Cheers
Sam Tang
Biochemistry Programme, School of Life Sciences, CUHK
participants (4)
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Luca Jovine
-
luzuok
-
Sam Tang
-
Terwilliger, Thomas Charles