Dear Patrick, Of course this is the best-first choice! I got confused with the names in my previous email. I was reffering to Chen when I mentioned the screens.
Kindly, On Wed, Jul 12, 2017 at 12:48 PM, Olga Moroz <olga.mo...@york.ac.uk> wrote: > MMS (microseed matrix screening) into several screens, as Patrick > suggested earlier, would be the first choice for me. > Works very often. > > Good luck! > > Olga > > > On 12 Jul 2017, at 08:48, Frank von Delft <frank.vonde...@sgc.ox.ac.uk> > wrote: > > The point I was failing to make: reducing either protein or precipitant > concentration will indeed reduce nucleation, but often won't get you bigger > or more single crystals: it will just make the appearance of crystals less > reliable. > > The way to get big single reliable crystals is to *increase* protein and > *greatly* reduce precipitant. > > (Even better: do seeding. Like Vicky said. Incredible how often people > don't bother to do seeding, yet it solves so many problems.) > > phx > > > On 12/07/2017 07:50, Vicky Tsirkone wrote: > > Dear Frank, > > I may see in the attached pic several nucleation points and a considerable > amount of microcrystals. Based to my knowledge decreasing the concentration > of the precipitant and/or the protein concentration would be a reasonable > approach to refine the initial hits. > By checking the diagram as you correctly mentioned you may see that the > fine tuning of protein and precipitant concetration may lead to the > desirable result without reaching the precipitation zone. > > Patrick just check your screens. Just a rule of thumb, if you see > precipitation in the ~60% of your drops then you should definitely reduce > the protein concentration. > > ps dont forget to try the *streak seeding*, as well. > > Have a nice day and again good luck. > > Vicky > > On Wed, Jul 12, 2017 at 8:50 AM, Frank von Delft < > frank.vonde...@sgc.ox.ac.uk> wrote: > >> Actually, you should try *increasing* the protein concentration - a >> lot. But be prepared to drop the precipitant concentration to almost >> nothing (1 or 2% isn't "low"). >> >> To understand why, look at the phase diagram and what we assume about >> vapour diffusion. (Which I'm assuming is what you're doing.) >> >> >> On 12/07/2017 06:28, Vicky Tsirkone wrote: >> >> Dear Patrick, >> >> You may reduce the protein concentation, as well. >> Another option could be the *streak seeding* by exploiting the drop of >> your initial condition. >> >> Good luck, >> >> V.T. >> >> On Mon, Jul 10, 2017 at 7:17 PM, Patrick Shaw Stewart < >> patr...@douglas.co.uk> wrote: >> >>> >>> Microseed them into two or three random screens. >>> >>> Search for MMS and rMMS online. >>> >>> Good luck >>> >>> Patrick >>> >>> >>> >>> >>> On 10 July 2017 at 15:47, Liuqing Chen <519198...@163.com> wrote: >>> >>>> hello everyone! >>>> I get a condition (10% w/v PEG 6000, 100mm HEPES PH7.0) in which my >>>> protein grow small needle like crystals, how can i optimize it to get >>>> bigger crystals? the attach is the crystals figure. >>>> thanks in advance >>>> sincerely >>>> Liuqing Chen >>>> >>> >>> >>> >>> -- >>> patr...@douglas.co.uk Douglas Instruments Ltd. >>> Douglas House, East Garston, Hungerford, Berkshire, RG17 7HD, UK >>> Directors: Peter Baldock, Patrick Shaw Stewart >>> >>> http://www.douglas.co.uk >>> Tel: 44 (0) 148-864-9090 US toll-free 1-877-225-2034 >>> <%28877%29%20225-2034> >>> Regd. England 2177994, VAT Reg. GB 480 7371 36 >>> >> >> >> > > >
