Dear Aleix, what is in the buffer and crystallization conditions? I have seen anomalous signal at 0.99 angstroms because my crystallization conditions contain NaI. And F'' (I) is around 3 at this wavelength. I would follow Eleanor advice. OR Try to generate anomalous map if you can solve your structure by molecular replacement. I do not know about CCP4, but phenix.refine generate anomalous map coeff-s if you refine against anomalous data, i.e. I(+)/I(-)
Best wishes, пн, 18 мар. 2019 г. в 09:22, Eleanor Dodson < [email protected]>: > Can you find the position of the anom scatterer used SHELXC/D/E or some > other tool.There is no need to know the element name to use it for phasing! > Eleanor > > PS However the existence of an "anom signal" just meand that I+ differs > systematically from I- and there can be other experimental reasons for that > appearing.. > > On Fri, 15 Mar 2019 at 22:08, Nukri Sanishvili <[email protected]> wrote: > >> Hi Aleix, >> Can you describe how you did the fluorescence scan, or share the plot >> itself? I am asking this because you say you could discard Fe, Zn and As/Se >> but you don't say anything about Cu which is in between these elements. >> If you tried but could not discard Cu, then it could be your "Culprit". >> Best, >> Nukri >> >> On Fri, Mar 15, 2019 at 4:17 PM Aleix Tarrés Solé <[email protected]> >> wrote: >> >>> Dear colleagues: >>> Hereby, I would like to expose a problem I encountered during the data >>> processing of one of my crystals. Recently I collected a full dataset of a >>> native protein-DNA crystal at an energy of 12667KeV. To my surprise, after >>> processing with XDS I can see that I have significant values of anomalous >>> correlation up to 5 Angstrom resolution. Using the fluorescence scan on the >>> beam, I could discard the presence of the following heavy atoms that could >>> have ended up in my drop due to cross-contamination; Se, As, Fe, Zn and Pr. >>> So far, my attempts to use this dataset for phasing have been sadly >>> unsuccessful. I would like to know if somebody has experience in this kind >>> of problem and can gently help with some advices. >>> >>> Thank you all in advance >>> >>> Aleix >>> >>> >>> ------------------------------ >>> >>> 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 >> > > ------------------------------ > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 > -- Evgenii Osipov Laboratory for Biocrystallography, Department of Pharmaceutical Sciences, KU Leuven O&N2 ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
