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Dear Crystallographers, I am a beginner to solving structures by x-ray crystallography. Having collected a diffraction data set using laboratory source X-ray, I am now processing the data. I have integrated the data successfully with the program iMOSFLM using the space group P212121. During the process of scaling and merging intensities using Scala, I was confronted with the question of setting the resolution cutoff. To clear the doubts I had, I have read the below articles with great care: 1. How good are my data and what is the resolution? Evans and Murshdov, 2013. 2. Assessing and maximizing data quality in macromolecular crystallography. Karplus and Diederichs, 2015. Based on these articles it becomes very clear that I should set the resolution cutoff to a value at which CC1/2 reduces to 0.2-0.4 irrespective of the values of either Rmerge or I/sigI (prone to uncertainities). When I ran the program Scala using high resolution cutoffs ranging from 1.861 A (resolution at which data was collected) to 2.33 A, I observe that at 2.0 A, the CC1/2 is 0.582 (outer shell) but the CC1/2 increases to 0.722 at 1.861 A. The Karplus and Diederichs article clearly states that the CC1/2 is 1 at low resolution and drops down with increasing resolution. It also states that any anomaly should be carefully inspected. I request the community to kindly inspect the statistics and guide me in setting the optimum resolution cutoff. I have attached a pdf file containing the Scala outputs (statistics and a plot of correlation coefficients versus resolution) for your inspection. Thanks, Satvik