1 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 GACAGGGGAA ACUUUGUC LOOP1 9 10 Crystallography ? ? Angstroms 1 G O3' -7.190 -10.046 -1.559 2 A P -7.036 -8.576 -0.914 O3' -5.476 -8.081 4.235 3 C P -5.270 -6.536 4.649 O3' -0.758 -5.323 7.344 4 A P -0.601 -3.729 7.538 O3' 4.305 -1.527 7.527 5 G P 4.373 0.083 7.442 O3' 7.528 3.485 5.601 6 G P 6.897 4.970 5.577 O3' 8.420 8.337 1.773 7 G P 7.644 9.718 2.067 O3' 5.734 13.079 -1.357 8 G P 5.173 14.246 -0.399 O3' -0.647 15.135 -0.007 9 A P -0.621 16.291 1.117 O3' -1.797 12.773 4.986 10 A P -1.540 11.244 4.542 O3' -6.213 7.870 3.358 11 A P -5.982 6.526 2.501 O3' -9.410 5.628 -1.619 12 C P -8.847 4.260 -2.262 O3' -6.513 5.058 -7.206 13 U P -5.696 3.823 -7.841 O3' -0.930 3.324 -9.626 14 U P -0.512 1.781 -9.832 O3' 4.830 0.787 -9.286 15 U P 5.226 -0.770 -9.422 O3' 9.391 -2.673 -6.611 16 G P 9.458 -4.259 -6.897 O3' 10.676 -7.590 -2.878 17 U P 10.454 -9.189 -2.860 O3' 9.916 -12.753 0.806 18 C P 9.630 -14.143 0.041 O3' 5.847 -17.357 2.028 1 18 + + c 2 17 - - c 3 16 + + c 4 15 - - c 5 14 W W c 6 13 W W c 7 12 + + c 8 11 S H t 7 11 ! ! ! 1 18 8 SG1 9 10 1 157.535 0.000 2 157.535 65.639 3 157.535 131.279 4 157.535 196.918 5 157.535 262.558 6 157.535 328.197 7 157.535 393.837 8 157.535 459.476 9 126.599 550.000 10 30.935 550.000 11 0.000 459.476 12 0.000 393.837 13 0.000 328.197 14 0.000 262.558 15 0.000 196.918 16 0.000 131.279 17 0.000 65.639 18 0.000 0.000