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Figure 3
The Wilson ratio 〈F2/〈I〉 (bottom) and the average intensity ratio 〈I2〉/〈I2 (top) calculated in resolution ranges for twinned data from crystals of gpD with α = 0.36 (blue lines) and IL-1β with α = 0.34 (red lines). As a control, the analogous values for the untwinned accurately measured data from lysozyme in space group P43212 (Dauter et al., 1999BB9) are shown in green. Only non-centrosymmetric reflections were included. The theoretically expected values for the Wilson ratio 〈F2/〈I〉 are 0.785 (untwinned) and 0.885 (perfectly twinned) and for the 〈I2〉/〈I2 ratio are 2.0 (untwinned) and 1.5 (perfectly twinned) and are marked as thin black lines. These tests are suggestive of twinning, but the graphs are too noisy for quantitative estimation of the twinning fraction.

Journal logoBIOLOGICAL
ISSN: 1399-0047
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