On 02/15/12 12:41, Jacob Keller wrote:
Are there any all-D proteins out there, of known structure or
otherwise? If so, do enantiomer-specific catalyses become inverted?
JPK
What do you mean by "Out There"? If you mean in the PDB, then yes. As
of two weeks ago, there are ~ 14 racemic structures deposited; most in
space group P -1, with one outlier in space group I -4 C 2. This
includes RNA, DNA, and PNA, but 6 entries are actually protein. The
longest is over 80 residues.
Theoretically, enantiomer-specific catalysis ought to be inverted, but
most of the structures solved are not enzymes. kaliotoxin, plectasin,
antifreeze protein, monellin, villin, and a designed peptide.
On the other hand, if by "out there" you meant in nature outside of
biochemistry and organic chemistry labs; then no, I am not aware of any
all-D proteins. There are a few protein/peptides which include a small
number of D-residues, which is marked up to nonribosomal synthesis.
The first paper I managed to Google:
http://jb.asm.org/content/185/24/7036.full
Learning from Nature's Drug Factories: Nonribosomal Synthesis of
Macrocyclic Peptides
doi: 10.1128/JB.185.24.7036-7043.2003 J. Bacteriol.December 2003 vol.
185 no. 24 7036-7043
If racemic crystallization isn't exciting enough for you, look into
quasi-racemic crystallization./
/
On Wed, Feb 15, 2012 at 8:05 AM, David Schuller<[email protected]> wrote:
Wukovitz& Yeates (1995) Nature Struc. Biol. 2(12): 1062-1067
predicts that the most probable space group for macromolecular
crystallization is P -1 (P 1-bar). All you have to do to try it out is
synthesize the all-D enantiomer of your protein and get it to fold properly.
On 02/14/12 18:36, Prem Kaushal wrote:
Hi
We have a protein that crystallized in P21212 space group. We are looking
for some different crystal forms. We tried few things did not work. Now we
are thinking to mutate surface residues. Anybody aware of any software which
can predict the mutations that might help in crystallizing protein in
different space group, please inform me.
Thanks in advance
Prem
--
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All Things Serve the Beam
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David J. Schuller
modern man in a post-modern world
MacCHESS, Cornell University
[email protected]
