Hi All:
I asked which small peptide is good for 3D structure study by NMR last
week. I really appreciate responses from Xiaohong Liu, Sudha
Veeraraghavan and Roger Kautz. Joseph Vaughn asked me to post the
response. Here are the emails:
*************
Hi,
How about Ubiquitin. I think you buy N15 labelled or fully labelled.
****************************************************
You will want to check out www.rcsb.org and www.bmrb.wisc.edu to find
best candidates.
Sudha Veeraraghavan
******************************************
Frank,
I used to know this, so I ran your question past John Osterhaut (He's
currently in Arizona, formerly of the Rowland Institute, spends his life
designing peptides that form structures other than helices, and so knows
the helix peptides without being biased).
>Rogerrrr,
>
>
>All the short peptides I know about form about 50% helix which makes
them
>not so good in the NOE quantitation department. Most people buy a
small
>protein that is maximally soluble. Ubiquitin (zillions of 2- 3- 4-
5-D NMR
>experiments run on this with various forms of labeling) or lysozyme
(it's
>cheap and you can dissolve a couple of hundred mgs per ml -- nice
strong
>signals) or some such. Something like BPTI - 53 amino acids and
stable like
>a rock might work. He doesn't say if he wants it labeled or not.
>
>
>There are some 18mer or so peptides which are alleged to be near 100%
>helical. You can't buy these. I think Earle Stellwagon and Neville
>Kallenbach published (separately) about these.
>
>
>Finally, the bee venom peptide, apamin, is available commercially (it
might
>be expensive). It is 17 amino acids and has a couple of disulfide
bonds
>which stabilize the helix.
>
>
>More information is needed to discern the requirements of this
>fellow. If he wants to set up experiments which will work with
proteins
>later he might want to use something that has a rototational
correlation
>time like a protein (a protein, for instance) instead of something
tiny.
>
>
>Personal air-conditioning by pouring ice water down one's pants and/or
>margaritas down one's throat is too prevalent here to make liq. N2 a
real
>threat.
>
>
>The last thing I remember before I woke up here was
The names I remember active in helical peptides were Bill DeGrado,
and Lynn Regan (now at Yale). (These are just the ones I met, ten
years
ago. Many of their students would have their own labs by now.)
Melittin was another bee venom peptide which is probably commercially
available. David Eisenberg was active with it.
Note the ones you can't buy you can have synthesized ($10 per residue
per 5
mg is $200/sample).
If you can't find a helix which is structured enough you might consider
zinc finger peptides which are also small, have a couple of turns of
helix,
and are stapled into a well-defined structure by chelating a Zn or other
divalent cation. Jeremy Berg (Johns Hopkins) is one of many who has
published about them.
-- Roger
***********************************************
Frank
--
Zhe (Frank) Zhou, Ph.D.
Co-Director of NMR Research Center
College of Basic Sciences, Louisiana State University
Baton Rouge, LA 70803, USA
Email: zzhou1_at_lsu.edu
Office: (225)-578-3460
Fax: (225)-578-3458
http://www.chem.lsu.edu/htdocs/people/fzhou/nmrweb/11.htm
Received on Tue May 28 2002 - 17:36:30 MST