depending on the importance of the project, I would be tempted to just
wait for the crystals to grow, and in the meantime:
- work on another project
- start a new project
- write a grant application, a paper, a review...
or a combination of the above.
Mark
Quoting William Scott <[log in to unmask]>:
> Dear James:
>
> It is extremely hard to make generalizations, but if it takes months for
> crystals to appear, the following questions are worth asking:
>
> 1. Is the actual concentration of macromolecule, precipitating agent, etc
> required for crystallization higher than what you are using? A closed
> vapor diffusion chamber is somewhat permeable to water vapor, and in the
> course of five months, you could easily lose half of the water. Try
> doubling the protein concentration, or crank up the concentration of one
> or more components in the reservoir solution.
>
> 2. Is the actual macromolecule you crystallized the same as what you
> started with? Slow degradation, or proteolysis, may be taking place, and
> the crystals you are growing are something else. (Similarly, if you have
> a cofactor or coenzyme, as these could slowly decompose into the critical
> ingredient for crystallization).
>
> 3. It might be too cold, and warming things up a bit might speed up
> crystallization.
>
> Hopefully that will get you started before the experts reply.
>
> Bill
>
>
>
>
>
> On Sun, October 11, 2009 8:27 am, james09 pruza wrote:
>> Dear crystallographers,
>>
>> Sorry for the non-ccp4 query. I am new to this field and need some
>> suggestions. My question is, why some protein takes longer time to
>> crystallize, say 6-8 months, and it is the only condition to get the
>> crystals.? What are the ways to get the crystals faster.
>>
>> The crystal appears with 60% of 2-Methyl, 2-4 Pentane Diol and only at 4
>> degree with very low concentration of NaCl. I have got some of the
>> sugggestions earlier from the CCP4-discussion board for microseeding, but
>> it
>> did not work.
>>
>> All suggestions from the experts are welcome.
>>
>> Thanks.
>> James
>>
>
>
>
> William G. Scott
>
> Contact info:
> http://chemistry.ucsc.edu/~wgscott/
>
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