Re: [ccp4bb] Problem with getting Rfree and Rf down

- Protein crystallography

Main steps:

- Protein purification
- Crystallisation

Special:

- Programs for crystallography
- X-ray detectors

Basic tutorials:

   - Chemistry
   - Protein
   - Peptide
   - Amino Acids

Xtal community:

- CCP4BB

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Problem with getting Rfree and Rf down
From: Sam Arnosti meisam {- dot -} nosrati {- at -} GMAIL {- dot -} COM
Date: 2012-01-23

Next message:
Subject: Re: Problem with getting Rfree and Rf down
From: Yuri Pompeu yuri {- dot -} pompeu {- at -} UFL {- dot -} EDU
Date: 2012-01-24

Subject: Re: Problem with getting Rfree and Rf down
From: Ed Pozharski epozh001 {- at -} UMARYLAND {- dot -} EDU
Date: 2012-01-23

These R-values are reasonable:

http://xray.bmc.uu.se/gerard/supmat/rfree2000/plotter.html

On Mon, 2012-01-23 at 21:48 +0000, Sam Arnosti wrote:
> Hi every one
>
> I have some crystals in the space group P3121. I collect 180 frames of data.
>
> My crystals do not diffract better than at most 2.0 angstrom, but the Rf barely goes below 23%,
>
> and Rfree also remains somewhere between 28-33%. I have tried to refine my data as much as I can.
>
> I do not know whether the problem is because of the bad diffraction or collecting extra frames.
>
> The structure factors are also high but they get better as the crystals diffract better.
>
> Thanks
>
> Sam

--
After much deep and profound brain things inside my head,
I have decided to thank you for bringing peace to our home.
Julian, King of Lemurs

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Problem with getting Rfree and Rf down
From: Sam Arnosti meisam {- dot -} nosrati {- at -} GMAIL {- dot -} COM
Date: 2012-01-23

Next message:
Subject: Re: Problem with getting Rfree and Rf down
From: Yuri Pompeu yuri {- dot -} pompeu {- at -} UFL {- dot -} EDU
Date: 2012-01-24