could try reverse matrix seed
On Sun, Apr 18, 2010 at 10:46 PM, tat cheung cheng <[email protected]> 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 > > > > > -- Pius S Padayatti Scientist, Polgenix, Inc. 11000 Cedar Ave, Suite 260 Cleveland, OH 44106 Phone: 216-658-4528 Fax: 216-658-4529
