Something that is missing from your list is a remarkable device pictured
as figure 2 in:
Perutz, M. (1985) "Early days of protein crystallography." /Methods in
Enzymology/ *114* 3-18
<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=4079771>.
which is actually a reproduction of figure 5 from:
J. D. Bernal and I. Fankuchen (1941) J. Gen. Physiol., 25, 111-146.
This cell is not difficult to make. I made one using a plastic ring (to
replace the brass) glued to an iron nut (to attach to the goniometer
magnet), a piece of Scotch Tape for the exit window and the cover slip
from the hanging drop setup of interest as the entrance window. All you
do is move the cover slip from the tray to the ring and then mount it
up. The excess vacuum grease from the tray makes the seal. Maybe put
~10 uL of well solution on the inner edge of the ring before closing it
to keep the humidity stable. The background (especially from glass) is
high but you have the advantage of never touching the crystal before
shooting it. We do use this device from time to time at the beamline.
I thought I had invented something new until I saw Perutz's paper. It
was then that I realized that my "invention" was one of the FIRST mounts
ever used to get diffraction from a protein crystal:
J. D. Bernal and D. Crowfoot (1934) Nature (London) 133, 794.
-James Holton
MAD Scientist
cedric bauvois wrote:
> hello all,
>
> I would like to thank everyone for all suggestions.
>
> Summary:
>
> 1 - MiTeGen Tools - MicroRT™ Room Temperature Mounting System
> - crystals slipping ? (suggestion of juan: amongst other things,
> problem resolved by using micromesh loops instead of using standard loops)
> - uses polyester capillary which scatters xrays less than the glass
> - works quite well
> - everyting is reasonably airtight
> - much easier to do than the old way.
>
> links:
> http://www.jenabioscience.com/cms/en/1/catalog/733_microrttrade_room_temperature_mounting_system.html
> http://mitegen.com/products/micrort/micrort.shtml
>
> 2 - coat the crystal with paratone oil and mount the crystal in a
> standard cryoloop
> - no special tools required
> - you can use the same crystal to collect under cryo-conditions and
> directly compare the impact of cooling the crystal
>
> 3 - the free mounting system (FMS) from Proteros Biostructures: a
> humidity control device
> - it does not have highly volatile components in the conditions
> - room temperature not too difficult
>
> links:
> http://www.proteros.com/articles.php?sid=18&lang=de
> <http://www.proteros.com/articles.php?sid=18&lang=de>
> contact: [log in to unmask] <mailto:[log in to unmask]>
>
> 4 - the humidifier device HC1b
> - developed at the EMBL
> - available at ESRF
> - easy to use
>
> links:
> http://www.esrf.eu/UsersAndScience/Experiments/MX/special-setup
> technical information: [log in to unmask] <mailto:[log in to unmask]>
>
> 5 - test crystal directly on plate
>
> - japan
>
> http://journals.iucr.org/d/issues/2002/10/01/issconts.html
> http://www.labo.co.jp/contents/direct_ex.html
> contact: [log in to unmask] <mailto:[log in to unmask]>
>
> - France, Grenoble
>
> explanations
> http://www.natx-ray.com/products/G-Rob_2D.html
> the movie
> http://www.natx-ray.com/products/G-Rob_2D_movie.html
> a prototype, commercialized by Natx-ray, is available on FIP beamline
> (http://www.esrf.eu/exp_facilities/BM30/).
> contact: [log in to unmask] <mailto:[log in to unmask]>
>
> Best regards,
> Cédric
>
> --
> Dr. Cedric Bauvois
> Cristallographie des protéines
> Institut de Recherches Microbiologiques JM Wiame -IRMW
> Av E. Gryzon 1, 1070 Brussels (Belgium)
> tél: +32 (0)2 5273634
> fax: +32 (0)2 5267273
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