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Dear Cheng, 

You could take your non-diffracting needle urchins and crush them in their growth solution (vortex several minutes and/or try Hampton seed bead).  Then make serial dilutions of the seed solution and add them to a whole new screen (the MMS method) or try the optimization method with new drops of fresh protein plus microseeds.  Maybe you will get thicker crystals or a different, better-diffracting form.

See below;

Acta Crystallogr D Biol Crystallogr. 2007 Apr;63(Pt 4):550-4. Epub 2007 Mar 16.

An automated microseed matrix-screening method for protein crystallization.

D'Arcy A, Villard F, Marsh M.

Novartis Institutes of Biomedical Research, Protease Platform, Klybeckstrasse 144, CH 4002 Basel, Switzerland. [log in to unmask]

Abstract

A microseed-matrix procedure has been established with the aim of influencing the nucleation event in standard crystallization screens. The method is based on the original description of matrix seeding described by Ireton & Stoddard (2004, Acta Cryst. D60, 601-605). Seed stocks are produced using a simple "seed-bead" method. The protein, reservoir solutions and seed stocks are pipetted simultaneously using a three-bore dispensing tip in drops of 0.6 microl total volume. The number and type of hits produced with the proteins tested in this study has been increased and it is believed that this method could be generally applicable to proteins where little or no nucleation is normally observed.





On Mon, Apr 19, 2010 at 3:18 PM, Phoebe Rice <[log in to unmask]> wrote:
Move the beam stop back?  My lab has grown quite a few
crystals that only diffract to very low resolution.
 Phoebe (with sympathy!)


---- Original message ----
>Date: Mon, 19 Apr 2010 11:35:11 +0800
>From: tat cheung cheng <[log in to unmask]>
>Subject: [ccp4bb] Re： [ccp4bb] Mysterious Crystals?
>To: [log in to unmask]
>
>   Thank you. Forget to mention, no diffraction
>   observed no matter with or without cyro cooling.
>
>     ------------------------------------------------
>
>   寄件人﹕ "[log in to unmask]" <[log in to unmask]>
>   收件人﹕ [log in to unmask]
>   傳送日期﹕ 2010/4/19 (一) 11:29:38 AM
>   主題： RE: [ccp4bb] Re： [ccp4bb] Mysterious
>   Crystals?
>
>   Hello Tc,
>
>
>
>   It isn’t that unusual to get protein crystals that
>   don’t diffract.  This happens probably 50% of the
>   time.  One can try dehydration of the crystals,
>   crystal annealing and additive screens to see if any
>   of these things will give you some diffraction.  In
>   addition, you didn’t mention whether you froze
>   these crystals- one should also try putting a
>   crystal in the beam without cryo-cooling, as
>   cryo-cooling can often be detrimental to
>   diffraction.
>
>
>
>   Cheers, tom
>
>
>
>   ----------------------------------------------------
>
>   From: CCP4 bulletin board
>   [mailto:[log in to unmask]] On Behalf Of tat
>   cheung cheng
>   Sent: Monday, 19 April 2010 1:26 PM
>   To: [log in to unmask]
>   Subject: [ccp4bb] Re： [ccp4bb] Mysterious
>   Crystals?
>
>
>
>   Yes, I have just done that. They are protein. But if
>   they are protein, why no diffraction? That's
>   intriguing.
>
>
>
>   ----------------------------------------------------
>
>   寄件人﹕ Jürgen Bosch <[log in to unmask]>
>   收件人﹕ [log in to unmask]
>   傳送日期﹕ 2010/4/19 (一) 10:57:40 AM
>   主題： Re: [ccp4bb] Mysterious Crystals?
>   Fish and wash some crystals then run them on a
>   SDS-gel, then you will know for sure if it's protein
>   or not.
>
>
>
>   J僡gen
>
>   On Apr 18, 2010, at 10:46 PM, tat cheung cheng
>   wrote:
>
>   Hi all,
>
>   I have got some crystals, the purified protein was
>   in Tris buffer with 300mM NaCl for crystallization.
>   they grew in light weight PEG, PEG400 or monomethyl
>   ethyl PEG500, they were needle shaped, could be long
>   (~0.2mm) but very thin all the time and sometimes
>   grew into sea-urchin like needle cluster.
>   What interesting is, when i gridded crystallization
>   conditions against pH or PEG amount, the crystals
>   sizes and shapes varied, and the crystals were
>   fragile so i believed they were protein crystals in
>   nature. But upon X-ray diffraction, they gave no
>   reflection at all, not even a faint spot.
>   I wonder, beside silly mistakes like misalignment of
>   the crystal to the beam, not enough exposure time,
>   what could be the reason for this mysterious
>   crystals? Are they protein or PEG or what?
>   Thanks very much.
>
>   Tc
>
>
>
>   -
>
>   J僡gen Bosch
>
>   Johns Hopkins Bloomberg School of Public Health
>   Department of Biochemistry & Molecular Biology
>   Johns Hopkins Malaria Research Institute
>   615 North Wolfe Street , W8708
>   Baltimore , MD 21205
>   Phone: +1-410-614-4742
>   Lab:      +1-410-614-4894
>   Fax:      +1-410-955-3655
>   http://web.mac.com/bosch_lab/
>
>
>
>
>
>
Phoebe A. Rice
Assoc. Prof., Dept. of Biochemistry & Molecular Biology
The University of Chicago
phone 773 834 1723
http://bmb.bsd.uchicago.edu/Faculty_and_Research/01_Faculty/01_Faculty_Alphabetically.php?faculty_id=123

RNA is really nifty
DNA is over fifty
We have put them
 both in one book
Please do take a
 really good look
http://www.rsc.org/shop/books/2008/9780854042722.asp