Under the supplied equal-scatterer model, which protein has lower normalized scattering I(q)/I(0) at q=0.5 nm^-1? Calculate both values from the coordinates. At q=1.0 nm^-1, for which protein(s) does the stated Guinier-validity rule permit a prediction? Give qRg for both and predict intensity only where the rule permits.

Coordinates are in angstrom (1 nm = 10 angstrom). XYZ atom rows are one-based after the two header lines. Use the supplied coordinate snapshots without optimization, crystallographic symmetry expansion or periodic wrapping. These are explicitly selected-site models, not complete all-atom or solution-ensemble models. S0006 contains all 76 C-alpha carbon sites of 1UBQ chain A: row i is residue A:i (i=1..76). S0007 contains all 46 C-alpha sites of 1CRN chain A: row i is residue A:i (i=1..46). Each site has equal weight. Do not use mass weights or add waters/side chains. Assume each CA is an identical point scatterer in a rigid isolated molecule, random orientations, no intermolecular interactions, hydration or solvent correction. This is a conditional model, not an experimental SAXS prediction. Rg^2=(1/N)sum_i||r_i-rbar||^2, with rbar the centroid. Use I(q)/I(0)=exp(-q^2 Rg^2/3). For this task, only apply the approximation if qRg<1.1 (strict). Use Rg in nm and q in nm^-1; outside the rule report not supported, not zero scattering.

Attachment S0006:
76
Coordinates in angstrom; atoms numbered from 1.
C 26.266 25.413 2.842
C 26.850 29.021 3.898
C 26.235 30.058 7.497
C 26.772 33.436 9.197
C 28.605 33.965 12.503
C 27.691 37.315 14.143
C 30.225 38.643 16.662
C 29.607 41.180 19.467
C 31.422 43.940 17.553
C 28.978 43.960 14.678
C 31.191 42.012 12.331
C 29.542 39.020 10.653
C 31.720 36.289 9.176
C 30.505 33.884 6.512
C 31.677 30.275 6.639
C 31.220 27.341 4.275
C 30.288 24.245 6.193
C 28.468 20.940 5.980
C 25.829 19.825 8.494
C 28.054 16.835 9.210
C 30.796 19.083 10.566
C 31.398 19.064 14.286
C 31.288 22.201 16.417
C 35.031 21.722 17.069
C 35.590 21.945 13.302
C 33.533 25.097 12.978
C 35.596 26.715 15.736
C 38.794 25.761 13.880
C 37.471 27.391 10.668
C 36.731 30.570 12.645
C 40.269 30.508 14.115
C 41.718 30.022 10.643
C 39.808 32.994 9.233
C 39.676 35.547 12.072
C 42.345 34.269 14.431
C 40.226 33.716 17.509
C 41.461 30.751 19.594
C 38.817 28.020 19.889
C 39.063 28.063 23.695
C 37.738 31.637 23.712
C 34.738 30.875 21.473
C 31.200 30.329 22.780
C 28.762 29.573 19.906
C 25.034 30.170 20.401
C 22.126 29.062 18.183
C 18.443 29.143 19.083
C 19.399 29.894 22.655
C 21.550 26.796 23.133
C 25.349 26.872 23.643
C 26.826 24.521 21.012
C 29.015 21.657 22.288
C 32.262 20.670 20.514
C 31.568 16.962 19.825
C 28.108 17.439 18.276
C 27.574 18.192 14.563
C 25.594 21.109 13.072
C 22.924 18.583 12.025
C 22.418 17.638 15.693
C 21.079 21.149 16.251
C 19.065 21.352 12.999
C 21.184 24.263 11.690
C 20.081 24.773 8.033
C 21.656 26.847 5.240
C 21.907 30.563 5.881
C 21.419 30.253 9.620
C 23.212 32.762 11.891
C 25.149 31.609 14.980
C 26.179 34.127 17.650
C 29.801 34.145 18.829
C 30.479 35.369 22.374
C 34.145 35.472 23.481
C 35.161 34.174 26.896
C 38.668 35.502 27.680
C 40.873 33.802 30.253
C 41.845 36.550 32.686
C 40.373 39.813 33.944


Attachment S0007:
46
Coordinates in angstrom; atoms numbered from 1.
C 16.967 12.784 4.338
C 13.856 11.469 6.066
C 13.660 10.707 9.787
C 10.646 8.991 11.408
C 9.448 9.034 15.012
C 8.673 5.314 15.279
C 8.912 2.083 13.258
C 5.145 2.209 12.453
C 5.598 5.767 11.082
C 8.496 4.609 8.837
C 6.500 1.584 7.565
C 3.545 3.935 6.751
C 5.929 6.358 5.055
C 7.331 3.607 2.791
C 3.782 2.599 1.742
C 2.890 6.285 1.126
C 5.895 6.489 -1.213
C 4.933 3.431 -3.326
C 2.792 5.376 -5.797
C 5.366 8.191 -6.018
C 3.767 10.609 -3.513
C 6.143 13.513 -2.696
C 8.114 13.103 0.500
C 6.614 16.317 1.913
C 3.074 14.894 1.756
C 4.180 11.549 3.187
C 5.879 13.502 6.026
C 2.691 15.221 7.194
C 0.715 12.045 6.657
C 2.986 9.994 8.950
C 4.769 12.336 11.360
C 8.140 11.694 9.635
C 10.280 14.760 8.823
C 12.552 15.877 6.036
C 15.930 17.454 6.941
C 18.635 18.861 4.738
C 21.452 16.969 6.513
C 22.019 13.242 7.020
C 21.936 12.911 10.809
C 18.504 12.312 12.298
C 17.924 13.421 15.877
C 17.334 10.956 18.691
C 13.564 11.573 18.836
C 13.257 10.745 15.081
C 15.445 7.667 15.246
C 13.512 5.395 12.878