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Tutorial 4

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Molecular replacement

AMoRe - more involved examples

The correlation coefficients and Rfactors as they came out of the simple AMoRe example are not particularly promising. It is, therefore, wise to play around with some of the parameters.

Do not worry about the jumping of windows. Whenever only a shape of a window comes up, position it on the screen where you want it (as before).

Varying the size and/or shape of the model cell

The Interface calculates an optimal size and shape for the model cell (see AMoRe Rotation Function Radius and Model Cell): 91.146 61.096 61.406 in this case. Opinions differ as to the values to use (see AMoRe Program Documentation). The Interface uses Navaza's method.

The parameters to change in the Interface, are
Model cell x, y and z in the 'Rotation Function Parameters' folder.
It would also be wise to increase the number of peaks output by decreasing the threshold fraction of maximum peak height to 0.3 both in the Rotation Function and Translation Function Parameters folders. Find 8 peaks above this fraction is probably enough to get an idea of the influence of noise peaks.

Evaluation

Results of various runs of auto-AMoRe, keeping the sphere volume at 19.396, are summarised in the following table. The resolution range used is 10-3Å. The model is as before.

model cell ROTFUN FITFUN comments
peak nrCC_FRF_FCC_ICC_P peak nrCC_FRF_FCC_I
calculated 122.553.035.029.2 283.226.883.2
223.452.836.329.2 1
38.156.913.612.7 824.155.024.0
49.856.514.512.2 330.153.028.0
101 101 101 122.653.035.129.4 283.226.883.2
223.452.836.329.4 1
38.056.913.512.5 824.054.425.2
49.856.614.512.2 329.853.227.9
91 91 91 122.553.035.029.1 283.226.883.2
2 3
323.452.835.029.1 1
48.156.913.712.4 724.154.924.0
59.856.614.512.2 429.853.227.9
61 61 61 122.853.035.426.7 283.226.883.2
223.752.736.726.7 1
38.356.914.112.3 524.154.924.8
49.856.614.411.6 329.953.227.9
31 31 31 123.052.835.315.1 383.326.883.3
224.152.437.014.9 183.226.883.2
323.252.836.114.9 2
48.457.212.910.6 424.255.123.4
21 21 21 118.254.228.011.6 483.326.883.2
27.757.211.210.7 623.555.121.0
321.453.333.410.4 383.226.883.2
422.153.234.510.4 2
5 1
69.856.714.29.6 526.254.024.8
20 20 20 120.153.931.311.1 383.326.883.3
220.253.731.510.9 283.226.883.2
320.753.632.310.9 1
48.457.111.69.9 723.855.522.2
510.056.715.49.1 429.552.927.7
19 19 19 16.257.78.19.4 3622.355.320.2 correct solutions not found in the standard search
27.757.210.58.5 1122.855.521.9
2914.655.322.37.0 183.326.883.3
3713.455.721.36.8 2
18 18 18 19.157.114.810.2 225.954.624.7 only 1 correct solution found, from 100 ROTFUN peaks
26.357.77.89.0 3422.955.019.8
2713.955.620.96.9 183.326.883.2
11 11 11correct solution not found within first 100 ROTFUN peaks
91 31 31 124.152.537.025.7 183.226.883.2
223.752.736.725.7 2
38.457.212.911.2 424.954.822.4
59.656.614.310.4 329.952.627.4
91 19 19 115.555.223.58.5 283.326.883.2
211.956.016.98.5 383.226.983.1
35.657.77.38.5 721.455.529.7
514.255.722.88.2 183.326.883.3

Conclusions

Coming soon.

More information

For more information on the AMoRe program, see AMoRe.

The Interface documentation on features from this tutorial can be found at:

Molecular Replacement Module
File Selection
The FileViewer Utility
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