Hi Eswar
Firstly, I would certainly try crystal seeding into random screens if
you haven't already tried it. Refs below.
Secondly, it's very convenient to grow the crystals under oil, and to
soak the organic solvents into the drops, through the oil. This makes
it much easier to harvest the crystals because the oil becomes
saturated with the solvent and stops it from evaporating when you pick
up the crystals. This approach can be used at the screening stage too.
See Mortuza, et al. High-resolution structure of a retroviral capsid
hexameric amino-terminal domain. Nature 431 (2004), pp 481-485. Also
see http://www.douglas.co.uk/winner1.htm
Good luck
Patrick
________
Allan D’Arcy, Frederic Villarda, May Marsh. 'An automated microseed
matrix-screening method for protein crystallization'. Acta
Crystallographica section D63 (2007) 550–554. On-line at
http://scripts.iucr.org/cgi-bin/paper?S0907444907007652
A. G. Villaseñor, A. Wong, A. Shao, A. Garg, A. Kuglstatter and S. F.
Harris. 'Acoustic matrix microseeding: improving protein crystal
growth with minimal chemical bias.' Acta Crystallographica Section D66
(2010) 568-576. On-line at
http://scripts.iucr.org/cgi-bin/paper?S0907444910005512
Galina Obmolova,* Thomas J. Malia, Alexey Teplyakov, Raymond Sweet and
Gary L. Gilliland. 'Promoting crystallization of antibody–antigen
complexes via microseed matrix screening.' Acta Crystallographica
Section D66 (2010) 927–933. Open-access at
http://journals.iucr.org/d/issues/2010/08/00/bw5361/bw5361.pdf
Patrick D. Shaw Stewart, Stefan A. Kolek, Richard A. Briggs, Naomi E.
Chayen and Peter F.M. Baldock. 'Getting the most out of the random
microseed matrix-screening method in protein crystallization'. Cryst.
Growth Des., 2011, 11 (8), pp 3432–3441. On-line at
http://pubs.acs.org/doi/abs/10.1021/cg2001442
See also http://www.douglas.co.uk/mms.htm
On Fri, Aug 26, 2011 at 11:55 AM, eswar reddy <[log in to unmask]> wrote:
>
> Dear All
> I was working on a Human protein and expression and solubility is good in E.coli and purification is One step (His-Tag), and i need to cleave the Histag before screens, if not the protein will precipitated and Aggregated, but after trying for 1.2 years i have crystals and they are with Organic solvents, (10 conditions), these crystals are inter grown like broccoli shaped and i tried seeding, but it is not successful, and even i tried with additive screen but the result is the same .... is there is any idea to increase the size and shape of my protein crystals.
> Any suggestions will be helpful for me
> Thanks in Advance
>
>
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