HI debashish ,
These crystal might be spherulites. You can try
reducing protein concentration in this situation and Microseeding will be
the best idea for this. You should crush these crystals by using seed
bead or needles and do either seeding with full screen or dilution or
streak seeding with low concentration of protein.
I had positive experience with these type of spherulites.
good luck with your seeding
vandna
On Thu, Sep 12, 2013 at 9:42 AM, Debasish Kumar Ghosh
<[log in to unmask]>wrote:
> Hi,
>
> I am working with a protein which can assume different oligomerization
> forms, starting from monomers to trimers and even penta-decamers. We
> conformed this by Native PAGE and HPLC studies. The protein's theoretical
> monomeric molecular weight is 14.6 KDa (pI - 5.9) and it has some 140 amino
> acids with high Glutamic acid (24), Lysine (10) and Arginine (13) content.
> I have tried to crystallize it but not getting any hit as far now.
> Previous study showed that this protein gets some stability by Calcium
> ion. With the calcium chloride conditions, I am getting spherical shaped
> structures, but not sure what are they; calcium chloride crystals or
> protein crystals. Can protein crystals be spherical in shape, specially
> when the protein behaves like an oligomer?
> Also please let me know what is the minimum protein concentration required
> to obtain crystal for such small protein (if there is any empirical
> rule/idea).
> Any suggestion will be highly appreciated.
>
> Thanks and regards,
> Debasish Kumar Ghosh
>
> CSIR- Junior Research Fellow (PhD Scholar)
> C/o: Dr. Akash Ranjan
> Computational and Functional Genomics Group
> Centre for DNA Fingerprinting and Diagnostics
> Hyderabad, INDIA
>
> Email(s): [log in to unmask], [log in to unmask]
> Telephone: 0091-9088787619 (M), 0091-40-24749396 (Lab)
> Lab URL:
> http://www.cdfd.org.in/labpages/computational_functional_genomics.html
>
--
Vandna Kukshal
Postdoctral Research Associate
Dept. Biochemistry and Molecular Biophysics
Washington University School of Medicine
660 S. Euclid, Campus Box 8231
St. Louis, MO 63110
