Re: [ccp4bb] RE : [ccp4bb] Strange diffraction image
Hi, Thanks for answering my question. I think I'd better provide more informations. These four images were taken from one crystals. The distance of image1-2 is 250mm, and image3-4 is 100mm. I checked more than 10 crystals and results were similar. The spots look very large. The lowest resolution is about 6A. As my protein can hydrolyze ATP, so protein buffer with 5mM of ATP. There is 0.2M of MgCl2 in precipitant buffer with PH7.0. 0.06M of CsCl can improve quality of crystals. I also setup control, in which target protein was not added, and could get nothing in it. I don't think it is a protein crystal. But salt spot should not be so large. And the rings are not just ice-ring. As I got crystal first in hampton crystal screen kit with MgCl2, TrisHCl and PEG4,000, there are only rings in images from 5-6A to about 3A. 2012/10/12 THOMPSON Andrew andrew.thomp...@synchrotron-soleil.fr: Hi Chang No mention of the resolution limit / oscillation range (I think I can see an ice ring, so I would guess 2.5 A?), but it looks like salt to me, with some weaker satellite peaks that may be something weird like an incommensurate phase. Did you try to index? Cheers Andy De : CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] de la part de Chang Qing [robie0...@gmail.com] Date d'envoi : vendredi 12 octobre 2012 08:11 À : CCP4BB@JISCMAIL.AC.UK Objet : [ccp4bb] Strange diffraction image Hi, everyone: I just got some strange diffraction images from crystals with triangular pyramid shape. I think this should not be protein diffraction. I never saw so strange images like this. Does anyone know what it is? Is it a kind of salt diffraction? Thank you very much Chang
Re: [ccp4bb] RE : [ccp4bb] Strange diffraction image
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Dear Chang, What makes you think spots from salt crystals should not be as large? You have got an ordinary small molecule crystal (or probably a cluster of them) in the beam, with a unit cell somewhat bigger than that of ice judging by the extra real ice rings you've got. Hydrolysis of ATP and Mg2+ present - it's probably (Mg)3(PO4)2- it is very unsoluble http://en.wikipedia.org/wiki/Solubility_table. Best, Tim On 10/12/2012 09:29 AM, Chang Qing wrote: Hi, Thanks for answering my question. I think I'd better provide more informations. These four images were taken from one crystals. The distance of image1-2 is 250mm, and image3-4 is 100mm. I checked more than 10 crystals and results were similar. The spots look very large. The lowest resolution is about 6A. As my protein can hydrolyze ATP, so protein buffer with 5mM of ATP. There is 0.2M of MgCl2 in precipitant buffer with PH7.0. 0.06M of CsCl can improve quality of crystals. I also setup control, in which target protein was not added, and could get nothing in it. I don't think it is a protein crystal. But salt spot should not be so large. And the rings are not just ice-ring. As I got crystal first in hampton crystal screen kit with MgCl2, TrisHCl and PEG4,000, there are only rings in images from 5-6A to about 3A. 2012/10/12 THOMPSON Andrew andrew.thomp...@synchrotron-soleil.fr: Hi Chang No mention of the resolution limit / oscillation range (I think I can see an ice ring, so I would guess 2.5 A?), but it looks like salt to me, with some weaker satellite peaks that may be something weird like an incommensurate phase. Did you try to index? Cheers Andy De : CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] de la part de Chang Qing [robie0...@gmail.com] Date d'envoi : vendredi 12 octobre 2012 08:11 À : CCP4BB@JISCMAIL.AC.UK Objet : [ccp4bb] Strange diffraction image Hi, everyone: I just got some strange diffraction images from crystals with triangular pyramid shape. I think this should not be protein diffraction. I never saw so strange images like this. Does anyone know what it is? Is it a kind of salt diffraction? Thank you very much Chang - -- - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iD8DBQFQeAheUxlJ7aRr7hoRAibDAJ9yAfiSwNmh8R4tGwUIwFEZno2qWACfStCM y+xKb+FGGglmv8lTL9Ej8ZQ= =ub/P -END PGP SIGNATURE-
Re: [ccp4bb] Fwd: [ccp4bb] RE : [ccp4bb] Strange diffraction image
Dear Chang, i have seen ATP diffraction, it's not very different of your image. Maybe you have only ATP in your crystals? Best regard Nicolas Le 12/10/12 14:56, Chang Qing a écrit : Dear Tim I think your explanation is logical. But I tried ADP as ligand first and got crystals and diffraction. ATP in additive kit was found to improve the quality of crystals from cluster to single crystal. CsCl can go on improving the quality and finally I got crystals like this. Is it possible that I get some strange crystals such as CsMgCl3 or something else? Best regard Chang -- Forwarded message -- From: Tim Gruene t...@shelx.uni-ac.gwdg.de Date: 2012/10/12 Subject: Re: [ccp4bb] RE : [ccp4bb] Strange diffraction image To: Chang Qing robie0...@gmail.com 抄送： CCP4BB@jiscmail.ac.uk -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Dear Chang, What makes you think spots from salt crystals should not be as large? You have got an ordinary small molecule crystal (or probably a cluster of them) in the beam, with a unit cell somewhat bigger than that of ice judging by the extra real ice rings you've got. Hydrolysis of ATP and Mg2+ present - it's probably (Mg)3(PO4)2- it is very unsoluble http://en.wikipedia.org/wiki/Solubility_table. Best, Tim On 10/12/2012 09:29 AM, Chang Qing wrote: Hi, Thanks for answering my question. I think I'd better provide more informations. These four images were taken from one crystals. The distance of image1-2 is 250mm, and image3-4 is 100mm. I checked more than 10 crystals and results were similar. The spots look very large. The lowest resolution is about 6A. As my protein can hydrolyze ATP, so protein buffer with 5mM of ATP. There is 0.2M of MgCl2 in precipitant buffer with PH7.0. 0.06M of CsCl can improve quality of crystals. I also setup control, in which target protein was not added, and could get nothing in it. I don't think it is a protein crystal. But salt spot should not be so large. And the rings are not just ice-ring. As I got crystal first in hampton crystal screen kit with MgCl2, TrisHCl and PEG4,000, there are only rings in images from 5-6A to about 3A. 2012/10/12 THOMPSON Andrew andrew.thomp...@synchrotron-soleil.fr: Hi Chang No mention of the resolution limit / oscillation range (I think I can see an ice ring, so I would guess 2.5 A?), but it looks like salt to me, with some weaker satellite peaks that may be something weird like an incommensurate phase. Did you try to index? Cheers Andy De : CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] de la part de Chang Qing [robie0...@gmail.com] Date d'envoi : vendredi 12 octobre 2012 08:11 À : CCP4BB@JISCMAIL.AC.UK Objet : [ccp4bb] Strange diffraction image Hi, everyone: I just got some strange diffraction images from crystals with triangular pyramid shape. I think this should not be protein diffraction. I never saw so strange images like this. Does anyone know what it is? Is it a kind of salt diffraction? Thank you very much Chang - -- - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iD8DBQFQeAheUxlJ7aRr7hoRAibDAJ9yAfiSwNmh8R4tGwUIwFEZno2qWACfStCM y+xKb+FGGglmv8lTL9Ej8ZQ= =ub/P -END PGP SIGNATURE-
Re: [ccp4bb] Fwd: [ccp4bb] RE : [ccp4bb] Strange diffraction image
Dear Nicolas ATP crystals is a reasonable answer. Thank you very much. Best regard Chang 2012/10/12 Nicolas Foos nicolas.f...@afmb.univ-mrs.fr: Dear Chang, i have seen ATP diffraction, it's not very different of your image. Maybe you have only ATP in your crystals? Best regard Nicolas Le 12/10/12 14:56, Chang Qing a écrit : Dear Tim I think your explanation is logical. But I tried ADP as ligand first and got crystals and diffraction. ATP in additive kit was found to improve the quality of crystals from cluster to single crystal. CsCl can go on improving the quality and finally I got crystals like this. Is it possible that I get some strange crystals such as CsMgCl3 or something else? Best regard Chang -- Forwarded message -- From: Tim Gruene t...@shelx.uni-ac.gwdg.de Date: 2012/10/12 Subject: Re: [ccp4bb] RE : [ccp4bb] Strange diffraction image To: Chang Qing robie0...@gmail.com 抄送： CCP4BB@jiscmail.ac.uk -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Dear Chang, What makes you think spots from salt crystals should not be as large? You have got an ordinary small molecule crystal (or probably a cluster of them) in the beam, with a unit cell somewhat bigger than that of ice judging by the extra real ice rings you've got. Hydrolysis of ATP and Mg2+ present - it's probably (Mg)3(PO4)2- it is very unsoluble http://en.wikipedia.org/wiki/Solubility_table. Best, Tim On 10/12/2012 09:29 AM, Chang Qing wrote: Hi, Thanks for answering my question. I think I'd better provide more informations. These four images were taken from one crystals. The distance of image1-2 is 250mm, and image3-4 is 100mm. I checked more than 10 crystals and results were similar. The spots look very large. The lowest resolution is about 6A. As my protein can hydrolyze ATP, so protein buffer with 5mM of ATP. There is 0.2M of MgCl2 in precipitant buffer with PH7.0. 0.06M of CsCl can improve quality of crystals. I also setup control, in which target protein was not added, and could get nothing in it. I don't think it is a protein crystal. But salt spot should not be so large. And the rings are not just ice-ring. As I got crystal first in hampton crystal screen kit with MgCl2, TrisHCl and PEG4,000, there are only rings in images from 5-6A to about 3A. 2012/10/12 THOMPSON Andrew andrew.thomp...@synchrotron-soleil.fr: Hi Chang No mention of the resolution limit / oscillation range (I think I can see an ice ring, so I would guess 2.5 A?), but it looks like salt to me, with some weaker satellite peaks that may be something weird like an incommensurate phase. Did you try to index? Cheers Andy De : CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] de la part de Chang Qing [robie0...@gmail.com] Date d'envoi : vendredi 12 octobre 2012 08:11 À : CCP4BB@JISCMAIL.AC.UK Objet : [ccp4bb] Strange diffraction image Hi, everyone: I just got some strange diffraction images from crystals with triangular pyramid shape. I think this should not be protein diffraction. I never saw so strange images like this. Does anyone know what it is? Is it a kind of salt diffraction? Thank you very much Chang - -- - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iD8DBQFQeAheUxlJ7aRr7hoRAibDAJ9yAfiSwNmh8R4tGwUIwFEZno2qWACfStCM y+xKb+FGGglmv8lTL9Ej8ZQ= =ub/P -END PGP SIGNATURE-
