Dear Frank, It is difficult to say something without the diffraction images but probably they are detergent ( or lipid) crystals. These crystals are in general "soft" and don't diffract well.
My suggestion is to know well what your crystals really are before any optimization. Best, Isabel ------------------------------------------------------------ Dr Isabel De Moraes, MRSC Membrane Protein Laboratory Diamond Light Source Ltd, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire, OX11 ODE, UK ------------------------------------------------------------ On 23 Oct 2013, at 17:22, crystalboy wrote: > Hi CCP4BB Forks, > > In recently I got a membrane protein crystal in the quite normal > membrane protein crystallization conditions as other persons reported, > like PEG400 16-19%, pH 6.0-7.5, with 50 mM MgCl2 (in my case) by using > sitting drop method. These crystals are around 50-100 uM. They look > like trapezoid crystal. My problem is all of my crystals have not > diffraction in home source X-ray and just poor diffraction at > Synchrotron (lower than 20 A). My crystals like to appear on the > surface of the drop. Look like my crystals are quite light. I had > tried to use a needle to touch them. Unlike other protein crystal, my > crystal looks like quite "soft". When I touch it, it didn't crack, but > was bend or mashed. I had tried to do additive screen and detergent > screen. It seems they are not useful. > > Do anyone have good ideas to optimization these crystals? Thanks for > your suggestions. > > Frank [cid:7839c9ff-b567-4b4b-b191-07dc6c335f34@fed.cclrc.ac.uk] -- 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
