Use "random" microseeding to pick up new conditions, and work with those.
See http://www.douglas.co.uk/mms.htm and http://www.douglas.co.uk/MMS_proc.htm for theory, references and practical details On 24 May 2013 03:20, Urmi Dhagat <[email protected]> wrote: > Hi, > > I am working on a protein antibody complex which readily crystallizes > (crystals form overnight and grow over 2-3 days) in 0.1M Bicine pH 9, 10 % > PEG8000. The crystals are chunky - shaped like a parallelogram but they > diffract poorly to about 8 Å. > > I have tried the following to improve diffraction: > 1. Screen different temperatures 4°C - crystals have bad form and > 10°C crystals grow slower but diffraction does not improve. > 2. I have done an additive screen – A few hits came up like Yttrium > Chloride and Acetonitrile but they don’t improve diffraction either > 3. I have tried streak seeding this does not help either > 4. Tested different cryo protectants – MPD, PEG400, Ethylene glycol > and glycerol - 10 - 15% glycerol seems to work best > 5. Not sure if cryo protectant affects diffraction in this case – I > will look at room temp diffraction soon to rule this out. > 6. Typical diffraction images attached > > Does anyone have suggestions on what I could try to improve diffraction of > my crystals? > > > > Urmi Dhagat > St Vincent's Institute > > > -- [email protected] Douglas Instruments Ltd. Douglas House, East Garston, Hungerford, Berkshire, RG17 7HD, UK Directors: Peter Baldock, Patrick Shaw Stewart http://www.douglas.co.uk Tel: 44 (0) 148-864-9090 US toll-free 1-877-225-2034 Regd. England 2177994, VAT Reg. GB 480 7371 36
