Dear Muhammad, I had a similar case, and the crystals could indeed be optimized. A few things to check first,
1) How long does it take for the needles to appear? Sometimes, if the protein is degraded/ cleaved over time, a small population (possibly a fragment of the whole protein) from the heterogeneous mix can give similar crystals. Like Bryan had suggested, it is also very useful to check the mol wt. of the crystallized species through mass spect/ native page. But do make sure to give the crystals serial washes, so the test accounts for crystallizexd species, not the ones from surrounding condition. 2) If the crystals indeed contain the protein of interest, they can be used for various seeding methods. I've got results from both streak and micro seeding. Best, Tuhin. Tuhin Bhowmick Department of Physics Indian Institute of Science Bangalore: 560012 Email: [email protected] On Wed, Jul 11, 2012 at 12:34 AM, Bernhard Rupp (Hofkristallrat a.D.) < [email protected]> wrote: > > Always give up.**** > > ** ** > > ...definitely not the kind of guy I want to sit up front in an airliner…** > ** > > ** ** > > Best regards, BR**** > > -----------------------------------------------------------------**** > > Bernhard Rupp, ATP-B737, CFII-MEI**** > > Vienna Air International**** > > Professional Aviation Services**** > > 001 (925) 209-7429**** > > +43 (676) 571-0536**** > > [email protected]**** > > [email protected]**** > > http://www.vienna-air.com/ **** > > -----------------------------------------------------------------**** > > It is not your aptitude but your attitude**** > > that determines your altitude. (or your crystals)**** > > -----------------------------------------------------------------**** > > ** ** > > ** ** > > ** ** > > From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of > yybbll**** > > Sent: Tuesday, July 10, 2012 11:58 AM**** > > To: [email protected]**** > > Subject: Re: [ccp4bb] Crystal Optimization**** > > ** ** > > Hi, **** > > **** > > In my experience, it is very very very difficult to optimize this needle > like crystal. Always give up.**** > > **** > > Good luck!**** > > **** > > **** > > Dear All;**** > > Could somebody give a nice suggestion how the following type crystal could > **** > > be optimized, I almost tried everything.**** > > Crystal Image is attached**** > > Crystal condition: 20% w/v PEG3350 and 200mM NaCl.**** > > Thanks in advance**** > > Bashir**** > > -- **** > > Muhammad Bashir Khan**** > > ****************************************************** > > Structural Genome Consortium (SGC). University of Toronto**** > > Toronto, Canada**** >
