Here's another example: http://www.pdb.org/pdb/explore/explore.do?structureId=2F62 dimer with "His-tag-ears" without His6-tag this would not have been possible.
Jürgen On Jun 27, 2012, at 12:04 PM, Brad Bennett wrote: I think it was an N-terminal RGS-type His tag in 3O8Y (human lipoxygenase) that mediated crystal contacts with a symmetry related molecule. As I recall, this tag composed a B-strand that formed a nice interface with a "native" B-strand of the symmetry related molecule. Pretty cool... -Brad On Wed, Jun 27, 2012 at 11:00 AM, Phoebe Rice <[email protected]<mailto:[email protected]>> wrote: With Flp recombinase - DNA complexes, a C-terminal His tag triggered a different (but sadly not better) crystal form, and the His side chains packed against the bases at the end of a neighboring DNA duplex. ===================================== Phoebe A. Rice Dept. of Biochemistry & Molecular Biology The University of Chicago phone 773 834 1723<tel:773%20834%201723> http://bmb.bsd.uchicago.edu/Faculty_and_Research/01_Faculty/01_Faculty_Alphabetically.php?faculty_id=123 http://www.rsc.org/shop/books/2008/9780854042722.asp ---- Original message ---- >Date: Wed, 27 Jun 2012 10:14:58 -0400 >From: CCP4 bulletin board ><[email protected]<mailto:[email protected]>> (on behalf of "R. M. >Garavito" <[email protected]<mailto:[email protected]>>) >Subject: Re: [ccp4bb] The effect of His-tag location on crystallization >To: [email protected]<mailto:[email protected]> > > Most of the comments you will get will be anecdotal > in that people will report the successful results > and do not take the time or effort to characterize > the less successful results. This often occurs > because the tagged portion of the protein is most > often disordered, even in the best crystals. Thus, > other than saying "tagging on this end works, but > tagging on that end doesn't," there is little more > you can say. Each case will be different, and it is > almost impossible to arrive at any generalized > conclusion. > We prefer C-terminal tagged proteins for a number of > reasons, but if an N-terminally tagged protein > crystallizes well, so be it. Of the dozens of N- > and C-tagged protein structures we have solved in my > lab and with collaborators, I have only seen one > case of an ordered His-tag: the His residues had > coordinated Cd ions, which proved essential for > getting good crystals. However, beyond that there > was not much more to say. > For your protein and the resulting crystals, an > N-terminally tagged protein crystallized well. > Whether you can draw any more conclusions from > these results depends on characterizing crystals of > both N- and C-tagged proteins. Just assuming that > the C-tagged protein is trying to crystallize in the > same or related crystal form as the N-tagged protein > is an unwarranted assumption without experimental > evidence to back it up. That is why most groups > just run with the winner. > Cheers, > Michael > **************************************************************** > R. Michael Garavito, Ph.D. > Professor of Biochemistry & Molecular Biology > 603 Wilson Rd., Rm. 513 > Michigan State University > East Lansing, MI 48824-1319 > Office: (517) 355-9724<tel:%28517%29%20355-9724> Lab: (517) > 353-9125<tel:%28517%29%20353-9125> > FAX: (517) 353-9334<tel:%28517%29%20353-9334> > Email: [email protected]<mailto:[email protected]> > **************************************************************** > On Jun 26, 2012, at 9:06 PM, weliu wrote: > > Dear all, > > We crystallized a protein and found that crystal > quality greatly depended on the location of > His-tag. When a His-tag was added at the > C-terminus, only crystalline precipitate or > spherical quasi crystals were grown. However, when > the His-tag was moved to the N-terminus, single > crystals were grown under a number of conditions, > and the best one diffracted to 1.7 angstrom after > optimization. I was wondering if there were > published reports describing similar cases. > > Thank you in advance > > Wei Liu ...................... Jürgen Bosch Johns Hopkins University Bloomberg School of Public Health Department of Biochemistry & Molecular Biology Johns Hopkins Malaria Research Institute 615 North Wolfe Street, W8708 Baltimore, MD 21205 Office: +1-410-614-4742 Lab: +1-410-614-4894 Fax: +1-410-955-2926 http://web.mac.com/bosch_lab/
