> They show a nice diffraction, but appear to be perfectly twinned. In most cases, structures can be solved (and biological questions answered) in twinned cases. I wouldn't be discouraged.
> I have crystallised a SeMet derivative, but I have not been able to collect > sufficiently good data, to get the phases. What is 'good' data to you? What are you considering as 'bad' data? > I am a beginner in crystallography, so all your suggestions would be precious > to me... You've come to the right place. Seek advice from people who have solved structures within the last 5 years using modern software. You'd be surprised how good the software for structure solution/refinement is these days. > Thus, I was thinking of trying with some heavy atom soaks. This by chance is not a metalloprotein is it? No covalently bound heavy metals? (maybe you have done some biochemistry and found some heavy metal requirement for activity, purification, etc) > which compounds and conditions would you advice as worth testing? If your native crystals diffract well on a home source, I would try soaking a fresh 500 mM solution of KI (iodide) for 5-10 seconds and collect the anomalous signal at home. If it kills your crystals, move to more toxic things... > > Thanks in advance, > > Federica > Cheers, F --------------------------------------------- Francis E. Reyes M.Sc. 215 UCB University of Colorado at Boulder
