1 23 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 GGACUGGGCG AGAAGUUUAG UCC LOOP1 11 13 Crystallography ? ? Angstroms 1 G O3' 4.267 12.231 -10.056 2 G P 4.092 10.771 -9.443 O3' 6.447 8.934 -4.283 3 A P 6.075 7.706 -3.342 O3' 5.054 7.788 2.394 4 C P 4.532 6.517 3.180 O3' 0.157 6.526 7.146 5 U P -0.378 5.065 7.474 O3' -5.259 3.667 8.241 6 G P -5.540 2.116 8.007 O3' -10.327 -0.507 6.013 7 G P -10.160 -2.068 5.769 O3' -13.096 -4.256 1.777 8 G P -12.607 -5.755 1.551 O3' -11.318 -8.983 -3.077 9 C P -10.904 -10.426 -2.535 O3' -6.885 -12.782 -5.359 10 G P -7.132 -14.170 -4.619 O3' -4.119 -14.844 0.239 11 A P -4.943 -15.341 1.514 O3' -3.503 -12.193 5.984 12 G P -3.663 -10.682 5.505 O3' 0.640 -7.450 6.686 13 A P 0.168 -6.145 5.906 O3' 4.536 -2.592 5.876 14 A P 6.000 -3.191 6.021 O3' 6.923 -4.645 1.722 15 G P 6.850 -3.241 0.991 O3' 5.408 -3.343 -4.911 16 U P 4.602 -2.176 -5.641 O3' 0.811 -3.127 -9.527 17 U P 0.060 -1.880 -10.178 O3' -5.527 -0.239 -10.612 18 U P -5.896 1.309 -10.571 O3' -10.462 4.169 -8.174 19 A P -12.006 4.304 -8.483 O3' -13.630 7.988 -4.211 20 G P -13.498 9.536 -3.866 O3' -12.759 12.120 1.318 21 U P -12.479 13.680 1.365 O3' -8.287 16.118 4.709 22 C P -7.731 17.599 4.553 O3' -2.043 19.028 4.446 23 C P -2.187 20.598 4.281 O3' 2.618 22.686 2.784 1 23 + + c 2 22 + + c 3 21 - - c 4 20 + + c 5 19 - - c 6 18 W W c 7 17 W W c 8 16 W W c 9 15 + + c 10 14 S H t 2 23 ! ! ! 10 12 ! ! ! 1 23 10 SG1 11 13 1 0.000 0.000 2 0.000 50.664 3 0.000 101.327 4 0.000 151.991 5 0.000 202.655 6 0.000 253.318 7 0.000 303.982 8 0.000 354.646 9 0.000 405.309 10 0.000 455.973 11 4.811 519.531 12 60.796 550.000 13 116.781 519.531 14 121.593 455.973 15 121.593 405.309 16 121.593 354.646 17 121.593 303.982 18 121.593 253.318 19 121.593 202.655 20 121.593 151.991 21 121.593 101.327 22 121.593 50.664 23 121.593 0.000