- I think the original poster was only calling attention to the fact
that some proteins want to be treated respectfully in order to
crystallise (and the fact that Rigaku Japan realises this). I find
that indeed the case.
Other proteins, however, prefer the attitude "I don't know why I am
setting up these drops, this protein is too crappy to crystallise",
i.e. a challenge.
Lysozyme, on the other hand, even crystallises under conditions of
complete indifference. At least I find that every student in a
practical course can get nice crystals of lysozyme, and a majority of
these drops have been set up under conditions of complete
indifference...maybe lysozyme is not a protein after all, but a salt:
lysozyme-chloride / LyCl7 ?
Mark
PS the detailed protocols and experiences are useful though.
Quoting Jeffrey Wilson <[log in to unmask]>:
> I was recently testing out the 30% PEGMME 5k, 0.1M NaOAc pH 4.5, 1M
> NaCl method mentioned in a Hampton Research catalog and attributed to
> Enrico Stura. I see that he has also just commented on this thread. I
> found that at 80mg/ml, batch with 1.5ul:1.5ul protein to precipitant
> ratio, lysozyme crystallized in about 1 hour. Jumping that up to
> 150mg/ml allowed for crystallization in minutes. Hanging drop behaved
> similarly. I was using lysozyme from Sigma.
>
> Jeff
>
> Jeffrey Wilson, Ph.D.
> University of Cincinnati College of Medicine
> Molecular Genetics Department
> 231 Albert Sabin Way
> MSB 3109A
> Cincinnati, OH 45267-0524
> (513) 558-1360
>
>
> On Dec 21, 2009, at 11:12 AM, MARTYN SYMMONS wrote:
>
>> Dear All
>> checking out the Lysozyme crystallization methods on the web I
>> liked the Rigaku Instructions that I found:
>> (http://www.rigaku.com/protein/crystallization.html)
>>
>> "...create a drop of 3ul lysozyme solution, and 3 ul of well
>> solution, respectfully, for a total drop size of 6ul..."
>>
>> So perhaps sometimes I am just not respectful enough to deserve crystals ?
>>
>> good wishes to all
>> regards,
>> Martyn
>> -----------------------
>> Martyn Symmons
>> MRC-MBU Cambridge UK
>> 'Chan fhiosrach mur feòraich.'
>> Gaelic proverb -
>> Nothing asked, nothing learned.
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