Hi Miguel, I was deliberately extreme, in order to make my point (which is that the only item that *really* needs to be stored is information).
Yes, it is in general cheaper to have plasmid samples stored on DNA cards. Total cost would be a few dollars depending on whether you use commercial DNA cards or make your own and also depending on how many replicates (DNA spots) one stores. The cost of sending DNA through the mail is also quite low, even for international shipments because it's a simple letter. The only significant cost is to transform the DNA off the card into suitable host organism and to verify its integrity (adviseable if DNA in question is several years old). On the other hand, one already can find DNA synthesis for less than 30 cents per bp. Since the company also does sequencing - the only remaining cost is that of subcloning and transformation/transfection etc. For a protein of say 400 amino acids it's about 1300 nt (given the ends and such) which comes out to be less than $500. If you're working with something hideous (again, like a GPCR) then your materials costs are likely to be orders of magnitude higher than that simply because detergents, synthetic ligands, etc. still cost a lot of money. Therefore DNA cost becomes relatively insignificant :) And that's now. In the future (and I mean near future) costs for DNA synthesis and sequencing are likely to drop - probably to about 5 cents per bp, ten years from now. So this is only going to get better. Artem --- When the Weasel comes to give New Year's greetings to the Chickens no good intentions are in his mind. -----Original Message----- From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of Miguel Ortiz Lombardia Sent: Sunday, March 22, 2009 4:58 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] Plasmids and other material [Was: images] Hi, I mostly agree with Artem, except on one point: > As long as people publish most of the details necessary to reproduce > the > materials (protein samples and crystals) used in structure > determination - > the crystals may be reproduced 'by persons skilled in the art'. > There is no > need to even store or distribute specific plasmid/clone DNA samples > any more > as long as relevant DNA sequences are retained (thank you, synthetic > DNA > providers!). I understand that it may look today like a romantic idea, but good science is done in labs that cannot easily pay the fees of those fancy synthetic DNA providers. Storage and distribution of this kind of material is therefore still important. Of course, there is a limit: you cannot be expected to send crystals all around the world, let aside other planets. In general, good common sense should be enough, from plasmids to images. As Eleanor pointed out, we should keep those materials available, because they are primarily our responsibility. Artem is right in that many reports simply don't provide enough information to reproduce the results. The most important reason to have such information is not to go against fraud, I am also an optimist here, but to be able to reproduce the results so that we can produce new results from them. This information should be in the papers or in 'supplementary files' or wherever. Some authors when contacted will be happy to provide you with the info, but others never answer your letters. Science should be about collaboration and trust, shouldn't it? That would make things easier and cheaper. Or we can implement rules and more rules like the security freaks do and we all suffer now when travelling. Best, Miguel -- Miguel Ortiz Lombardía Architecture et Fonction des Macromolécules Biologiques UMR6098 ( CNRS, U. de Provence, U. de la Méditerranée ) Case 932 163 Avenue de Luminy 13288 Marseille cedex 9 France Tel : +33(0) 491 82 55 93 Fax: +33(0) 491 26 67 20 e-mail: miguel.ortiz-lombar...@afmb.univ-mrs.fr Web: http://www.pangea.org/mol/spip.php?rubrique2 -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.
