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Re: [ccp4bb] Mysterious Crystals?

- Protein crystallography

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CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999
Previous message:
Subject: Mysterious Crystals?
From: tat cheung cheng theifire {- at -} YAHOO {- dot -} COM {- dot -} HK
Date: 2010-04-19
Next message:
Subject: Re: Mysterious Crystals?
From: tat cheung cheng theifire {- at -} YAHOO {- dot -} COM {- dot -} HK
Date: 2010-04-19


Subject: Re: Mysterious Crystals?
From: Jürgen_Bosch jubosch {- at -} JHSPH {- dot -} EDU
Date: 2010-04-19

Fish and wash some crystals then run them on a SDS-gel, then you will know for sure if it's protein or not.

Jürgen
On Apr 18, 2010, at 10:46 PM, tat cheung cheng wrote:

> Hi all,
>
> I have got some crystals, the purified protein was in Tris buffer with 300mM NaCl for crystallization. they grew in light weight PEG, PEG400 or monomethyl ethyl PEG500, they were needle shaped, could be long (~0.2mm) but very thin all the time and sometimes grew into sea-urchin like needle cluster.
> What interesting is, when i gridded crystallization conditions against pH or PEG amount, the crystals sizes and shapes varied, and the crystals were fragile so i believed they were protein crystals in nature. But upon X-ray diffraction, they gave no reflection at all, not even a faint spot.
> I wonder, beside silly mistakes like misalignment of the crystal to the beam, not enough exposure time, what could be the reason for this mysterious crystals? Are they protein or PEG or what?
> Thanks very much.
>
> Tc
>
>
>
>

-
Jürgen Bosch
Johns Hopkins Bloomberg School of Public Health
Department of Biochemistry & Molecular Biology
Johns Hopkins Malaria Research Institute
615 North Wolfe Street, W8708
Baltimore, MD 21205
Phone: +1-410-614-4742
Lab: +1-410-614-4894
Fax: +1-410-955-3655
http://web.mac.com/bosch_lab/


CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999
Previous message:
Subject: Mysterious Crystals?
From: tat cheung cheng theifire {- at -} YAHOO {- dot -} COM {- dot -} HK
Date: 2010-04-19
Next message:
Subject: Re: Mysterious Crystals?
From: tat cheung cheng theifire {- at -} YAHOO {- dot -} COM {- dot -} HK
Date: 2010-04-19



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