[ccp4bb] is it Ok to freeze
Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany
Re: [ccp4bb] is it Ok to freeze
Hi If you mean organic small molecules, then the opinion for the last 15 years at least is probably yes, unless you know you'll have a phase change. Most small molecule crystals don't have the same problems with needing cryoprotectants as macromolecules, due in large part to not having a large proportion of water in the lattice, so the process is somewhat more straightforward. Also, most small molecule crystals can be handled quite happily in the absence of mother liquor, and you don't have to worry about them drying out while transferring to the fibre (rather than loop) which would normally be used for mounting them. Of course, there are numerous exceptions to the most I'm referring to here. In most cases you'll get a substantially better structure at cryo temperatures (of course, what better means may be open to debate). On 19 Jun 2008, at 09:47, Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH
Re: [ccp4bb] is it Ok to freeze
Harry Can you clarify why you get a substantially better structure at cryo temperatures e.g higher intensity at high resolution due to reduction in B factors, reduction in radiation damage, anything else? Colin -Original Message- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of harry powell Sent: 19 June 2008 10:12 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] is it Ok to freeze Hi If you mean organic small molecules, then the opinion for the last 15 years at least is probably yes, unless you know you'll have a phase change. Most small molecule crystals don't have the same problems with needing cryoprotectants as macromolecules, due in large part to not having a large proportion of water in the lattice, so the process is somewhat more straightforward. Also, most small molecule crystals can be handled quite happily in the absence of mother liquor, and you don't have to worry about them drying out while transferring to the fibre (rather than loop) which would normally be used for mounting them. Of course, there are numerous exceptions to the most I'm referring to here. In most cases you'll get a substantially better structure at cryo temperatures (of course, what better means may be open to debate). On 19 Jun 2008, at 09:47, Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH DIVFONT size=1 color=grayThis e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail. Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd. Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message. Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom /FONT/DIV
Re: [ccp4bb] is it Ok to freeze
Hi Colin yes, both of those. Plus freezing out multiple conformations so you can model them properly - bear in mind that a small molecule structure at a resolution worse than 1Å would be challenging to get past the normal criteria of referees, so you should be able to see them at least some of the time (depending on how distinct the multiple conformations are). It may be easier to distinguish the atom type (C,N,O?) if you have a lower temperature dataset - at least 50% of the small molecule structures I did when I was working in that field were _not_ of the compound the chemist thought they had, so working out the atom type was rather important. However, I'm not sure this is a strong reason for doing cryo work on its own - any half decent modern automated small molecule structure solution program could do it with most room temperature datasets. Also, if you have an air-sensitive crystal (chemists say this as a shorthand when they mean more specific things like the chemical is oxygen or moisture-sensitive) you can slow the reactions down enough so that your crystal doesn't decompose because of those. But that's more of a problem with organometallics than organics, except with some of the more exotic organic species... And if your crystal loses solvent (e.g. I used to use CH2Cl2 (methylene chloride to the old hacks here) as a solvent, and that will just evaporate at room temp, leaving you with a powder rather than a beautiful single crystal. Although you can get round air-sensitivity and solvent loss by mounting in a capillary, there are good reasons to avoid that and cryo-cool with a naked (or semi-naked, dressed only in a gossamer- like film of perfluoropolyether oil) crystal if you can, as those of us who have done both regularly know. I'm sure there are other reasons why it would be substantially better, but I also know that there is considerable effort going into high-temperature devices, which will be used to help collect substantially better datasets for the crystals that their developers are interested in. does this help? On 19 Jun 2008, at 10:25, Nave, C (Colin) wrote: Harry Can you clarify why you get a substantially better structure at cryo temperatures e.g higher intensity at high resolution due to reduction in B factors, reduction in radiation damage, anything else? Colin -Original Message- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of harry powell Sent: 19 June 2008 10:12 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] is it Ok to freeze Hi If you mean organic small molecules, then the opinion for the last 15 years at least is probably yes, unless you know you'll have a phase change. Most small molecule crystals don't have the same problems with needing cryoprotectants as macromolecules, due in large part to not having a large proportion of water in the lattice, so the process is somewhat more straightforward. Also, most small molecule crystals can be handled quite happily in the absence of mother liquor, and you don't have to worry about them drying out while transferring to the fibre (rather than loop) which would normally be used for mounting them. Of course, there are numerous exceptions to the most I'm referring to here. In most cases you'll get a substantially better structure at cryo temperatures (of course, what better means may be open to debate). On 19 Jun 2008, at 09:47, Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH This e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail. Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd. Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message. Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom
Re: [ccp4bb] is it Ok to freeze
Hi I just noticed I scrambled that first paragraph. I didn't intend to imply you should be able to see your referees (or their criteria) at least some of the time. It should have read something more like- yes, both of those. Plus freezing out multiple conformations so that you can model them properly; you should be able to see them at least some of the time (depending on how distinct the multiple conformations are). Bear in mind that a small molecule structure at a resolution worse than 1Å would be challenging to get past the normal criteria of referees. On 19 Jun 2008, at 11:05, harry powell wrote: Hi Colin yes, both of those. Plus freezing out multiple conformations so you can model them properly - bear in mind that a small molecule structure at a resolution worse than 1Å would be challenging to get past the normal criteria of referees, so you should be able to see them at least some of the time (depending on how distinct the multiple conformations are). Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH
Re: [ccp4bb] is it Ok to freeze
Typically crystals of small organic compounds do not require freezing as there are no solvent channels. They do in general not suffer from radiation damage at room temperature the way protein crystals do. Occasionally they are mounted in a capillary instead of simply glueing them to a goniometer if they are air sensitive. In principle freezing should not damage the crystals, but one still may have to be carefull if the crystals are large. I think you risk increasing mosiacity, and any manipulation that is not needed will on average only reduce the quality of the specimen rather than improve it Remy Loris Vrije Univesiteit Brussel Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany
Re: [ccp4bb] is it Ok to freeze
Hi Without wishing to start an argument, I've been checking with some of my colleagues who are chemical crystallographers - the reply I get is that, for routine structural analysis, pretty well all datasets are collected at 100K unless the crystals fall apart at low T, or if the cryostream is broken. I should point out that the first production Cryostream that I came across (serial number 2, which I think may have been the first one sold!) was in the Cambridge Department of Chemistry in about 1985. They didn't become common until the mid-1990's in PX labs, when they were already well-established as a bit of pretty well essential kit for small molecule work. So although what Remy says is true, the practice is to cryocool most of the time. On 19 Jun 2008, at 12:08, Remy Loris wrote: Typically crystals of small organic compounds do not require freezing as there are no solvent channels. They do in general not suffer from radiation damage at room temperature the way protein crystals do. Occasionally they are mounted in a capillary instead of simply glueing them to a goniometer if they are air sensitive. In principle freezing should not damage the crystals, but one still may have to be carefull if the crystals are large. I think you risk increasing mosiacity, and any manipulation that is not needed will on average only reduce the quality of the specimen rather than improve it Remy Loris Vrije Univesiteit Brussel Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH
Re: [ccp4bb] is it Ok to freeze
This fellow below is presumably and Indian, writing in English at a German University, a very confused new generation researcher, indeed. Maybe this will help: S.Jayashankar (Ein wenig verwirrter Forscher der neuen Generation) Forschungsstudent Institut fuer Biophysikalische Chemie Medizinische Schule, Hannover (where is this?) Deutschland sorry for that :-) Marius Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany
Re: [ccp4bb] is it Ok to freeze
I would go along with Harry friends, I used crystal cooling when I was at Aafje Vos' Struktuurchemie lab in Groningen in 1972, when the technique had already been in routine use there for at least 10 years, in order to study compounds that are liquid at ambient temp (of course it was custom-built kit using a collection of liq N2 Dewar vessel tubes, nothing as fancy as a Cryostream!). The Groningen group really pioneered the use of low temp for small molecule structures and I don't recall increased mosaicity ever being an issue. Occasionally you would get a compound with a phase transition on the way down and the crystal would literally explode in a puff of powder before your eyes! The motive for using low temp was of course to reduce the thermal motion and libration effects, and thus greatly improve the accuracy of the molecular geometry, and low temp is pretty well essential if you're into valence density deformation maps, again in order the minimise the contribution from thermal motion. -- Ian -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of harry powell Sent: 19 June 2008 14:05 To: Remy Loris Cc: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] is it Ok to freeze Hi Without wishing to start an argument, I've been checking with some of my colleagues who are chemical crystallographers - the reply I get is that, for routine structural analysis, pretty well all datasets are collected at 100K unless the crystals fall apart at low T, or if the cryostream is broken. I should point out that the first production Cryostream that I came across (serial number 2, which I think may have been the first one sold!) was in the Cambridge Department of Chemistry in about 1985. They didn't become common until the mid-1990's in PX labs, when they were already well-established as a bit of pretty well essential kit for small molecule work. So although what Remy says is true, the practice is to cryocool most of the time. On 19 Jun 2008, at 12:08, Remy Loris wrote: Typically crystals of small organic compounds do not require freezing as there are no solvent channels. They do in general not suffer from radiation damage at room temperature the way protein crystals do. Occasionally they are mounted in a capillary instead of simply glueing them to a goniometer if they are air sensitive. In principle freezing should not damage the crystals, but one still may have to be carefull if the crystals are large. I think you risk increasing mosiacity, and any manipulation that is not needed will on average only reduce the quality of the specimen rather than improve it Remy Loris Vrije Univesiteit Brussel Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH Disclaimer This communication is confidential and may contain privileged information intended solely for the named addressee(s). It may not be used or disclosed except for the purpose for which it has been sent. If you are not the intended recipient you must not review, use, disclose, copy, distribute or take any action in reliance upon it. If you have received this communication in error, please notify Astex Therapeutics Ltd by emailing [EMAIL PROTECTED] and destroy all copies of the message and any attached documents. Astex Therapeutics Ltd monitors, controls and protects all its messaging traffic in compliance with its corporate email policy. The Company accepts no liability or responsibility for any onward transmission or use of emails and attachments having left the Astex Therapeutics domain. Unless expressly stated, opinions in this message are those of the individual sender and not of Astex Therapeutics Ltd. The recipient should check this email and any attachments for the presence of computer viruses. Astex Therapeutics Ltd accepts no liability for damage caused by any virus transmitted by this email. E-mail is susceptible to data corruption, interception, unauthorized amendment, and tampering, Astex Therapeutics Ltd only send and receive e-mails on the basis that the Company is not liable for any such alteration or any consequences thereof. Astex Therapeutics Ltd., Registered in England at 436 Cambridge Science Park, Cambridge CB4 0QA under number 3751674
Re: [ccp4bb] is it Ok to freeze
Every small molecule dataset I collected as a graduate student in chemistry back in the mid to late 1980's was at 100K. I never had to worry about crystal slippage during collection, organic solvent evaporation, air oxidation of the sample (organometallic metal clusters) or secondary radiation damage. When I switched to protein crystallography, I was absolutely amazed when told that you can not cool a protein crystal below 4 degrees C for data collection. How times have changed, Diana On Jun 19, 2008, at 9:03 AM, Ian Tickle wrote: I would go along with Harry friends, I used crystal cooling when I was at Aafje Vos' Struktuurchemie lab in Groningen in 1972, when the technique had already been in routine use there for at least 10 years, in order to study compounds that are liquid at ambient temp (of course it was custom-built kit using a collection of liq N2 Dewar vessel tubes, nothing as fancy as a Cryostream!). The Groningen group really pioneered the use of low temp for small molecule structures and I don't recall increased mosaicity ever being an issue. Occasionally you would get a compound with a phase transition on the way down and the crystal would literally explode in a puff of powder before your eyes! The motive for using low temp was of course to reduce the thermal motion and libration effects, and thus greatly improve the accuracy of the molecular geometry, and low temp is pretty well essential if you're into valence density deformation maps, again in order the minimise the contribution from thermal motion. -- Ian -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of harry powell Sent: 19 June 2008 14:05 To: Remy Loris Cc: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] is it Ok to freeze Hi Without wishing to start an argument, I've been checking with some of my colleagues who are chemical crystallographers - the reply I get is that, for routine structural analysis, pretty well all datasets are collected at 100K unless the crystals fall apart at low T, or if the cryostream is broken. I should point out that the first production Cryostream that I came across (serial number 2, which I think may have been the first one sold!) was in the Cambridge Department of Chemistry in about 1985. They didn't become common until the mid-1990's in PX labs, when they were already well-established as a bit of pretty well essential kit for small molecule work. So although what Remy says is true, the practice is to cryocool most of the time. On 19 Jun 2008, at 12:08, Remy Loris wrote: Typically crystals of small organic compounds do not require freezing as there are no solvent channels. They do in general not suffer from radiation damage at room temperature the way protein crystals do. Occasionally they are mounted in a capillary instead of simply glueing them to a goniometer if they are air sensitive. In principle freezing should not damage the crystals, but one still may have to be carefull if the crystals are large. I think you risk increasing mosiacity, and any manipulation that is not needed will on average only reduce the quality of the specimen rather than improve it Remy Loris Vrije Univesiteit Brussel Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH Disclaimer This communication is confidential and may contain privileged information intended solely for the named addressee(s). It may not be used or disclosed except for the purpose for which it has been sent. If you are not the intended recipient you must not review, use, disclose, copy, distribute or take any action in reliance upon it. If you have received this communication in error, please notify Astex Therapeutics Ltd by emailing [EMAIL PROTECTED] and destroy all copies of the message and any attached documents. Astex Therapeutics Ltd monitors, controls and protects all its messaging traffic in compliance with its corporate email policy. The Company accepts no liability or responsibility for any onward transmission or use of emails and attachments having left the Astex Therapeutics domain. Unless expressly stated, opinions in this message are those of the individual sender and not of Astex Therapeutics Ltd. The recipient should check this email and any attachments for the presence
Re: [ccp4bb] is it Ok to freeze
I typically collect data at -50C on all small molecule samples. I've had quite a few cases where there are phase transitions, and you can damage the crystals, especially when the molecules are packed in a pi-pi stacking motif, or I'm dealing with alloy systems. I've also collected data at 16K, so it all depends on your sample. Instead of finding out if there is a phase transition, -50C seems to be a good choice of a temperature to reduce the displacement amplitudes, radiation damage, and solvent loss. Bernie Santarsiero On Thu, June 19, 2008 9:40 am, Diana Tomchick wrote: Every small molecule dataset I collected as a graduate student in chemistry back in the mid to late 1980's was at 100K. I never had to worry about crystal slippage during collection, organic solvent evaporation, air oxidation of the sample (organometallic metal clusters) or secondary radiation damage. When I switched to protein crystallography, I was absolutely amazed when told that you can not cool a protein crystal below 4 degrees C for data collection. How times have changed, Diana On Jun 19, 2008, at 9:03 AM, Ian Tickle wrote: I would go along with Harry friends, I used crystal cooling when I was at Aafje Vos' Struktuurchemie lab in Groningen in 1972, when the technique had already been in routine use there for at least 10 years, in order to study compounds that are liquid at ambient temp (of course it was custom-built kit using a collection of liq N2 Dewar vessel tubes, nothing as fancy as a Cryostream!). The Groningen group really pioneered the use of low temp for small molecule structures and I don't recall increased mosaicity ever being an issue. Occasionally you would get a compound with a phase transition on the way down and the crystal would literally explode in a puff of powder before your eyes! The motive for using low temp was of course to reduce the thermal motion and libration effects, and thus greatly improve the accuracy of the molecular geometry, and low temp is pretty well essential if you're into valence density deformation maps, again in order the minimise the contribution from thermal motion. -- Ian -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of harry powell Sent: 19 June 2008 14:05 To: Remy Loris Cc: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] is it Ok to freeze Hi Without wishing to start an argument, I've been checking with some of my colleagues who are chemical crystallographers - the reply I get is that, for routine structural analysis, pretty well all datasets are collected at 100K unless the crystals fall apart at low T, or if the cryostream is broken. I should point out that the first production Cryostream that I came across (serial number 2, which I think may have been the first one sold!) was in the Cambridge Department of Chemistry in about 1985. They didn't become common until the mid-1990's in PX labs, when they were already well-established as a bit of pretty well essential kit for small molecule work. So although what Remy says is true, the practice is to cryocool most of the time. On 19 Jun 2008, at 12:08, Remy Loris wrote: Typically crystals of small organic compounds do not require freezing as there are no solvent channels. They do in general not suffer from radiation damage at room temperature the way protein crystals do. Occasionally they are mounted in a capillary instead of simply glueing them to a goniometer if they are air sensitive. In principle freezing should not damage the crystals, but one still may have to be carefull if the crystals are large. I think you risk increasing mosiacity, and any manipulation that is not needed will on average only reduce the quality of the specimen rather than improve it Remy Loris Vrije Univesiteit Brussel Jayashankar wrote: Dear Scientists and Friends, I am not sure, whether organic crystals need to be in cryo stream necessarily during data collection from an in house xray machine . How most of the organic crystals have been solved mostly? -- S.Jayashankar (A bit confused new generation researcher). Research Student Institute for Biophysical Chemistry Hannover Medical School Germany Harry -- Dr Harry Powell, MRC Laboratory of Molecular Biology, MRC Centre, Hills Road, Cambridge, CB2 2QH Disclaimer This communication is confidential and may contain privileged information intended solely for the named addressee(s). It may not be used or disclosed except for the purpose for which it has been sent. If you are not the intended recipient you must not review, use, disclose, copy, distribute or take any action in reliance upon it. If you have received this communication in error, please notify Astex Therapeutics Ltd by emailing [EMAIL
Re: [ccp4bb] is it Ok to freeze
Ha, everyone seems to be bragging about how far back cryo- crystallography really goes. In that vain, I'd like to mention that, in Martinsried, we had a room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. It was requested (demanded, really...) by Robert Huber when the Max-Planck Institute was finalized in 1972 (I hope I got my history right). That room contained an entire diffraction system. Talk about crystal cooling... bah, way too dinky. Cool the entire room! Of course, it was a hazard to work in that room, and so - as far as I know - there was only one post-doc from India how ever used it. That room had an ante-room with two more generators plus detectors that could be cooled down to -20°C! Ah, the good old Wild West times of macromolecular crystallography... Cheers - MM On Jun 19, 2008, at 11:48 AM, Pietro Roversi wrote: Well everyone, talking of early applications of cryocooling to X-ray crystallography, what about Sten Samson's marvellous helium cryostat which was operational at Caltech since the end of the 1970s and used to reach temperatures around 20 K routinely , see for example: Proc Natl Acad Sci U S A. 1982 Jul;79(13):4040-4. Structure of a B-DNA dodecamer at 16 K. Drew HR, Samson S, Dickerson RE. That instrument (and its twin) are now both with Riccardo Destro in Milano. Ciao! Pietro -- Pietro Roversi Sir William Dunn School of Pathology, Oxford University South Parks Road, Oxford OX1 3RE, England UK Tel. 0044-1865-275385 Mischa Machius, PhD Associate Professor Department of Biochemistry UT Southwestern Medical Center at Dallas 5323 Harry Hines Blvd.; ND10.214A Dallas, TX 75390-8816; U.S.A. Tel: +1 214 645 6381 Fax: +1 214 645 6353
Re: [ccp4bb] is it Ok to freeze
... room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. I'm trying to picture this ... did you guys have some kind of LN2- proof SCUBA diving equipment to work in there? Klaus - Klaus Fütterer, Ph.D. School of Biosciences P: +44-(0)-121-414 5895 University of Birmingham F: +44-(0)-121-414 5925 Edgbaston E: [EMAIL PROTECTED] Birmingham, B15 2TT, UK W: www.biochemistry.bham.ac.uk/klaus/ - On 19 Jun 2008, at 18:04, Mischa Machius wrote: Ha, everyone seems to be bragging about how far back cryo- crystallography really goes. In that vain, I'd like to mention that, in Martinsried, we had a room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. It was requested (demanded, really...) by Robert Huber when the Max-Planck Institute was finalized in 1972 (I hope I got my history right). That room contained an entire diffraction system. Talk about crystal cooling... bah, way too dinky. Cool the entire room! Of course, it was a hazard to work in that room, and so - as far as I know - there was only one post-doc from India how ever used it. That room had an ante-room with two more generators plus detectors that could be cooled down to -20°C! Ah, the good old Wild West times of macromolecular crystallography... Cheers - MM On Jun 19, 2008, at 11:48 AM, Pietro Roversi wrote: Well everyone, talking of early applications of cryocooling to X-ray crystallography, what about Sten Samson's marvellous helium cryostat which was operational at Caltech since the end of the 1970s and used to reach temperatures around 20 K routinely , see for example: Proc Natl Acad Sci U S A. 1982 Jul;79(13):4040-4. Structure of a B-DNA dodecamer at 16 K. Drew HR, Samson S, Dickerson RE. That instrument (and its twin) are now both with Riccardo Destro in Milano. Ciao! Pietro -- Pietro Roversi Sir William Dunn School of Pathology, Oxford University South Parks Road, Oxford OX1 3RE, England UK Tel. 0044-1865-275385 -- -- Mischa Machius, PhD Associate Professor Department of Biochemistry UT Southwestern Medical Center at Dallas 5323 Harry Hines Blvd.; ND10.214A Dallas, TX 75390-8816; U.S.A. Tel: +1 214 645 6381 Fax: +1 214 645 6353
Re: [ccp4bb] is it Ok to freeze
Sadly, I have never seen the room being used. Perhaps one of the 'older' Martinsrieder on the forum has seen it. MM On Jun 19, 2008, at 12:11 PM, Klaus Futterer wrote: ... room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. I'm trying to picture this ... did you guys have some kind of LN2- proof SCUBA diving equipment to work in there? Klaus - Klaus Fütterer, Ph.D. School of Biosciences P: +44-(0)-121-414 5895 University of Birmingham F: +44-(0)-121-414 5925 Edgbaston E: [EMAIL PROTECTED] Birmingham, B15 2TT, UK W: www.biochemistry.bham.ac.uk/ klaus/ - On 19 Jun 2008, at 18:04, Mischa Machius wrote: Ha, everyone seems to be bragging about how far back cryo- crystallography really goes. In that vain, I'd like to mention that, in Martinsried, we had a room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. It was requested (demanded, really...) by Robert Huber when the Max-Planck Institute was finalized in 1972 (I hope I got my history right). That room contained an entire diffraction system. Talk about crystal cooling... bah, way too dinky. Cool the entire room! Of course, it was a hazard to work in that room, and so - as far as I know - there was only one post-doc from India how ever used it. That room had an ante-room with two more generators plus detectors that could be cooled down to -20°C! Ah, the good old Wild West times of macromolecular crystallography... Cheers - MM On Jun 19, 2008, at 11:48 AM, Pietro Roversi wrote: Well everyone, talking of early applications of cryocooling to X-ray crystallography, what about Sten Samson's marvellous helium cryostat which was operational at Caltech since the end of the 1970s and used to reach temperatures around 20 K routinely , see for example: Proc Natl Acad Sci U S A. 1982 Jul;79(13):4040-4. Structure of a B-DNA dodecamer at 16 K. Drew HR, Samson S, Dickerson RE. That instrument (and its twin) are now both with Riccardo Destro in Milano. Ciao! Pietro -- Pietro Roversi Sir William Dunn School of Pathology, Oxford University South Parks Road, Oxford OX1 3RE, England UK Tel. 0044-1865-275385 Mischa Machius, PhD Associate Professor Department of Biochemistry UT Southwestern Medical Center at Dallas 5323 Harry Hines Blvd.; ND10.214A Dallas, TX 75390-8816; U.S.A. Tel: +1 214 645 6381 Fax: +1 214 645 6353 Mischa Machius, PhD Associate Professor Department of Biochemistry UT Southwestern Medical Center at Dallas 5323 Harry Hines Blvd.; ND10.214A Dallas, TX 75390-8816; U.S.A. Tel: +1 214 645 6381 Fax: +1 214 645 6353
Re: [ccp4bb] is it Ok to freeze
I've been in that cold room / hutch. I never heard of it being flushed with LN2. I think that is just to make the room sound cooler. Jim On Thu, 19 Jun 2008, Mischa Machius wrote: Sadly, I have never seen the room being used. Perhaps one of the 'older' Martinsrieder on the forum has seen it. MM On Jun 19, 2008, at 12:11 PM, Klaus Futterer wrote: ... room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. I'm trying to picture this ... did you guys have some kind of LN2-proof SCUBA diving equipment to work in there? Klaus
Re: [ccp4bb] is it Ok to freeze
Dick Dickerson tried to do the same thing at Caltech around the same time. The major problem with cooling equipment was that the Picker goniometer had lots of metal in it, and each of the metal pieces cooled and contracted differently, so the alignment was always off. Nice idea, but not useful. That's when they got the idea to just cool the sample. Yes, Sten Samson's device was elegant in a number of ways, and we could collect 16-20K data for weeks on it. Bernie Santarsiero On Thu, June 19, 2008 12:04 pm, Mischa Machius wrote: Ha, everyone seems to be bragging about how far back cryo- crystallography really goes. In that vain, I'd like to mention that, in Martinsried, we had a room that was lined with insulated steel walls and that could be flushed with liquid nitrogen. It was requested (demanded, really...) by Robert Huber when the Max-Planck Institute was finalized in 1972 (I hope I got my history right). That room contained an entire diffraction system. Talk about crystal cooling... bah, way too dinky. Cool the entire room! Of course, it was a hazard to work in that room, and so - as far as I know - there was only one post-doc from India how ever used it. That room had an ante-room with two more generators plus detectors that could be cooled down to -20°C! Ah, the good old Wild West times of macromolecular crystallography... Cheers - MM On Jun 19, 2008, at 11:48 AM, Pietro Roversi wrote: Well everyone, talking of early applications of cryocooling to X-ray crystallography, what about Sten Samson's marvellous helium cryostat which was operational at Caltech since the end of the 1970s and used to reach temperatures around 20 K routinely , see for example: Proc Natl Acad Sci U S A. 1982 Jul;79(13):4040-4. Structure of a B-DNA dodecamer at 16 K. Drew HR, Samson S, Dickerson RE. That instrument (and its twin) are now both with Riccardo Destro in Milano. Ciao! Pietro -- Pietro Roversi Sir William Dunn School of Pathology, Oxford University South Parks Road, Oxford OX1 3RE, England UK Tel. 0044-1865-275385 Mischa Machius, PhD Associate Professor Department of Biochemistry UT Southwestern Medical Center at Dallas 5323 Harry Hines Blvd.; ND10.214A Dallas, TX 75390-8816; U.S.A. Tel: +1 214 645 6381 Fax: +1 214 645 6353
