You may want to have a look at 3ur7 and 3ur8. I have also another example
of a glycohydrolytic enzyme with an N-terminal His-tag sitting in the
active site of a symmetry-related molecule (not deposited yet).
Karolina
On 27/6/2012, "Brad Bennett" <[log in to unmask]> 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 <[log in to unmask]> 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
>>
>> 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 <[log in to unmask]> (on behalf of "R. M.
>> Garavito" <[log in to unmask]>)
>> >Subject: Re: [ccp4bb] The effect of His-tag location on crystallization
>> >To: [log in to unmask]
>> >
>> > 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 Lab: (517) 353-9125
>> > FAX: (517) 353-9334
>> > Email: [log in to unmask]
>> > ****************************************************************
>> > 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
>>
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