1 27 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 GGCGUCACAC CUUCGGGUGA AGUCGCC LOOP1 13 14 Crystallography ? ? Angstroms 1 G P -37.500 -15.523 30.471 O3' -34.366 -10.715 29.778 2 G P -34.497 -9.257 29.072 O3' -30.253 -5.936 28.363 3 C P -30.466 -4.584 27.491 O3' -26.891 -2.489 24.176 4 G P -27.485 -1.137 23.503 O3' -25.420 0.871 18.858 5 U P -26.230 2.175 18.331 O3' -27.722 3.369 13.398 6 C P -28.727 4.642 13.256 O3' -32.645 4.746 9.352 7 A P -33.839 5.844 9.378 O3' -38.616 5.587 7.374 8 C P -38.820 7.192 7.404 O3' -42.724 9.772 9.756 9 A P -42.289 11.308 10.064 O3' -44.047 14.065 14.459 10 C P -43.398 15.521 14.776 O3' -42.363 17.385 19.801 11 C P -41.744 18.882 19.902 O3' -37.614 20.416 23.196 12 U P -36.727 21.761 22.885 O3' -31.060 21.886 22.482 13 U P -30.025 23.056 22.046 O3' -24.985 21.725 19.052 14 C P -25.080 22.254 17.520 O3' -27.174 18.788 13.083 15 G P -26.021 18.153 12.135 O3' -24.651 12.909 14.358 16 G P -25.145 11.386 14.659 O3' -26.475 8.363 19.715 17 G P -27.562 7.157 19.760 O3' -30.581 6.941 24.490 18 U P -31.662 5.732 24.622 O3' -36.748 6.809 26.394 19 G P -37.840 5.619 26.194 O3' -43.220 6.287 25.527 20 A P -43.606 4.778 25.987 O3' -44.772 0.258 22.975 21 A P -43.657 -0.604 22.158 O3' -45.852 -3.544 17.337 22 G P -45.308 -5.067 17.264 O3' -42.560 -6.713 13.097 23 U P -41.271 -7.664 13.351 O3' -37.603 -8.520 9.437 24 C P -36.600 -9.754 9.750 O3' -31.325 -9.582 8.906 25 G P -30.683 -10.941 9.525 O3' -25.375 -10.701 11.322 26 C P -24.741 -12.022 12.038 O3' -21.863 -9.991 17.067 27 C P -20.734 -10.280 18.206 O3' -21.133 -15.362 18.824 15 syn 1 27 + + c 2 26 + + c 3 25 + + c 4 24 + + c 5 24 W W c 6 22 + + c 6 23 W W c 8 19 + + c 9 18 - - c 10 17 + + c 11 16 + + c 12 15 S W t 8 21 ! ! ! 1 27 4 8 19 5 SG1 5 7 SG2 13 14 SG3 20 23 1 80.590 0.000 2 80.590 33.579 3 80.590 67.159 4 80.590 100.738 5 80.590 134.317 6 80.590 201.476 7 80.590 268.635 8 80.590 369.373 9 80.590 402.952 10 80.590 436.532 11 80.590 470.111 12 80.590 503.690 13 64.765 550.000 14 15.826 550.000 15 0.000 503.690 16 0.000 470.111 17 0.000 436.532 18 0.000 402.952 19 0.000 369.373 20 0.000 335.794 21 0.000 302.214 22 0.000 235.056 23 0.000 167.897 24 0.000 100.738 25 0.000 67.159 26 0.000 33.579 27 0.000 0.000