Re: [ccp4bb] Protein aggregation and crystallization
Hi, Anita If you could find a way to test the elute's activity/binding to its' substrat/cofactor, then you will learn much more about your target. If the function assay is elusive, you could try superose column (5KDa-5MKDa). Does your light scattering tell you about the estimated size and MW? Best, Joe On Sat, Aug 27, 2011 at 1:29 AM, anita p wrote: > Hi Yury, > I have done dynamic light scattering and it shows its polydispersed. > Please let me know if it is still ok for setting trays. > reg. > anita > > On Fri, Aug 26, 2011 at 10:21 PM, Yuriy Patskovsky < > yuriy.patskov...@einstein.yu.edu> wrote: > >> Anita, >> an assembly may be quite large - I would check it somehow, maybe by light >> scattering or centrifugation >> >> Good luck >> >> Yury >> -- >> *From:* CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] on behalf of anita p >> [crystals...@gmail.com] >> *Sent:* Friday, August 26, 2011 3:03 AM >> *To:* CCP4BB@JISCMAIL.AC.UK >> *Subject:* [ccp4bb] Protein aggregation and crystallization >> >> Hi All, >> I am working on a protein which has a membrane spanning region and as >> cytosolic domain.I have made various deletion constructs of the protein, so >> that I can have a crystallizable fragment. There is no homologues mentioned >> in the pdb for this protein. >> All of these constructs are purified successfully but when concentrated >> and loaded on a gel filtration column Superdex-200, they elute in the void >> volume. But the proteins donot precipitate out !! >> Is it worth while to go ahead for crystallization trials?? >> Any other suggestion is most welcome. >> Thanks >> Anita >> >> >
Re: [ccp4bb] Methods for dehydrating crystals
Dear Andrea check out: Post-crystallization treatments for improving diffraction quality of protein crystals. Heras B, Martin JL. Acta Crystallogr D Biol Crystallogr. 2005 Sep;61(Pt 9):1173-80. All the best Savvas On 26 Aug 2011, at 22:53, Andrea L Edwards wrote: > Hi all, > > What are the most successful methods you know of for dehydrating a crystal > prior to freezing it? I am trying to push the resolution of my crystals. > > Thanks, > Andrea
Re: [ccp4bb] Detergents to eliminate non specific aggregations
Hampton makes a "Detergent Screen" that works the same way as the Additive Screen. http://hamptonresearch.com/product_detail.aspx?cid=1&sid=39&pid=31 It has 96 unique detergent reagents for crystal screening. It is a bit expensive, but if you don't want to purchase the whole kit you could just download the formulation table and then you will have a nice long list of possibilities. Mike - Original Message - From: "商元" To: CCP4BB@JISCMAIL.AC.UK Sent: Saturday, August 27, 2011 4:55:27 AM GMT -08:00 US/Canada Pacific Subject: [ccp4bb] Detergents to eliminate non specific aggregations Hi, everyone, I can get my protein complex but there are some non-specific aggregation from the NMR spectra, and chaps can improve it. So, besides chaps, is there any other detergents to be used during crystal screening? All suggestions are welcome. Thanks&Regards, Yuan -- Michael C. Thompson Graduate Student Biochemistry & Molecular Biology Division Department of Chemistry & Biochemistry University of California, Los Angeles mi...@chem.ucla.edu
Re: [ccp4bb] reindexing monoclinic data
Sorry for adding confusion- of course in reciprocal space beta* should be acute. The figures should have been labeled a, c not h,L. Edward A. Berry wrote: Gregory Bowman wrote: Yes, but I don't actually want to swap a and c (convention that a is shorter than c), but instead flip k and keep h and l the same. Incidentally, it is not immediately obvious to me why in matrix I cited below that the new l is h+l: -1 0 0 0 -1 0 1 0 1 Greg Because -a and c would give acute beta angle, by convention should be obtuse?
Re: [ccp4bb] reindexing monoclinic data
Gregory Bowman wrote: Yes, but I don't actually want to swap a and c (convention that a is shorter than c), but instead flip k and keep h and l the same. Incidentally, it is not immediately obvious to me why in matrix I cited below that the new l is h+l: -1 0 0 0 -1 0 1 0 1 Greg Because -a and c would give acute beta angle, by convention should be obtuse? <>
[ccp4bb] Detergents to eliminate non specific aggregations
Hi, everyone, I can get my protein complex but there are some non-specific aggregation from the NMR spectra, and chaps can improve it. So, besides chaps, is there any other detergents to be used during crystal screening? All suggestions are welcome. Thanks&Regards, Yuan
