With improving techniques, we should always be making progress!
If we are trying to answer a biological question that is really important,
we would be better off
improving the purification, the crystallization, the cryo-conditions
instead of having to rely on
processing old images with new software.
I have 10 years worth of images. I have reprocessed very few of them and
never made any
sensational progress using the new software. Poor diffraction is poor
diffraction.
Money can be better spent buying a wine cellar, storage works for wine.
Enrico.
On Tue, 18 Oct 2011 14:51:27 +0200, Boaz Shaanan
<bshaa...@exchange.bgu.ac.il> wrote:
Hi Felix,
Excuse my question, but what have you discovered about lysozyme that we
haven't already known before which justifies all these efforts?
After all, we're mostly after finding solutions to biological problems,
aren't we?
Boaz
Boaz Shaanan, Ph.D.
Dept. of Life Sciences
Ben-Gurion University of the Negev
Beer-Sheva 84105
Israel
E-mail: bshaa...@bgu.ac.il
Phone: 972-8-647-2220 Skype: boaz.shaanan
Fax: 972-8-647-2992 or 972-8-646-1710
________________________________________
From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] on behalf of Felix
Frolow [mbfro...@post.tau.ac.il]
Sent: Tuesday, October 18, 2011 1:40 PM
To: CCP4BB@JISCMAIL.AC.UK
Subject: Re: [ccp4bb] IUCr committees, depositing images
I could not agree less. There is constant development of the software
for refinement that allow to do things that were not
possible or were not necessary in the past such as intelligent
refinement of occupancies of mutually exclusive sites, entities and
conformations.
I frequently remeasure lysozyme crystals. I use them as a test system
for the beam lines, new detectors, novel software developments,
refinement improvement etc. Sometimes I am collecting data in quite
different wavelength than of existing structures. And what about
diffraction data from a chemically modified lysozyme molecule?
They are good data that show evolution of the beam line stations if they
are keeper in historical order.
To store them all, or not to store at all…
Storage of the diffraction data is not a drinking club with muscle-bound
selectors outside :-)
Felix Frolow
Dr Felix Frolow
Professor of Structural Biology and Biotechnology
Department of Molecular Microbiology
and Biotechnology
Tel Aviv University 69978, Israel
Acta Crystallographica F, co-editor
e-mail: mbfro...@post.tau.ac.il
Tel: ++972-3640-8723
Fax: ++972-3640-9407
Cellular: 0547 459 608
On Oct 18, 2011, at 12:52 , Chris Morris wrote:
Some crystals are hard to make, so storing all the data the best way to
get reproducibility. On the other hand, no one needs more images of
lysozyme. So using the same standard for every deposition doesn't sound
right.
The discussion should be held on the basis of overall cost to the
research budget - not on the assumption that some costs can be
externalised. It is too easy to say "you should store the images, in
case I want to reprocess them sometime". IT isn't free, nor is it
always cheaper than the associated experimental work. The key
comparison is:
Cost of growing new crystals + cost of beam line time
With:
Cost of storing images * probability of processing them again
At present, detectors are improving more quickly than processing
software. Sample preparation methods are also improving. These forces
both press downward the probability that a particular image will ever
be reprocessed.
regards,
Chris
____________________________________________
Chris Morris
chris.mor...@stfc.ac.uk
Tel: +44 (0)1925 603689 Fax: +44 (0)1925 603634
Mobile: 07921-717915
Skype: chrishgmorris
http://pims.structuralbiology.eu/
http://www.citeulike.org/blog/chrishmorris
Daresbury Lab, Daresbury, Warrington, UK, WA4 4AD
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Enrico A. Stura D.Phil. (Oxon) , Tel: 33 (0)1 69 08 4302 Office
Room 19, Bat.152, Tel: 33 (0)1 69 08 9449 Lab
LTMB, SIMOPRO, IBiTec-S, CE Saclay, 91191 Gif-sur-Yvette, FRANCE
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