Dear Amala, 1. Hampton provides a precrystallisation screening kit which can be used to determine the protein concentration to be used for crystallisation.
2. Also if you observe the screening crystallisation plate, according to what I follow, at least there should be minimum 60 % of conditions where you should see protein precipitate. 3. Always prefer using homogeneous, freshly prepared protein at least for screening because certain protein don't behave well once freezed or stored for longer duration. Size exclusion chromatography can enhance your success rate. 4. Observe the screening plate atleast for 3 months after setting the trial. 5. Not all protein will give you crystals in initial screening. You will have to pick the promising conditions and optimise it further. Prefer optimising atleast 6-7 promising hits few of which may give you diffractable quality crystal. After all getting crystals for difficult proteins that diffract, requires lot of optimization, dedication, efforts, perseverance and luck. BEST OF LUCK. On Fri, 27 Dec 2019, 19:00 amala mathimaran, <amalat...@gmail.com> wrote: > Dear all, > > Can you suggest me how to get protein crystal??? > > > > I purified my target protein and concentrated to 12mg/ml (pI 6.04). Final > purified protein contains 50mM HEPES pH 8.0 and 50mM NaCl. Then the initial > screening was done using hanging drop method but no crystal. So 2mM NADP > cofactor was added again screen with Hampton (PEG ion, PEG RX, crystal > screen, Index) and Molecular dimensions conditions etc. I got precipitate > like formation the image was attached below. From this formation what I can > do… mean while I increase the protein concentration and did screening for > that selected conditions again I got same kind of formations. I am new to > protein crystallography kindly suggesting me. And how much concentration is > suitable for protein crystallization?? How to find which concentration is > enough for our target protein crystallization?? Thanks in advance > > ------------------------------ > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
