1 23 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 GGCGACGGUG UAAAAAUCUC GCC LOOP1 11 14 Crystallography ? ? Angstroms 1 G P -9.512 -17.662 4.272 O3' -11.964 -18.756 1.449 2 G P -12.886 -17.896 0.431 O3' -14.236 -19.408 -4.492 3 C P -15.355 -18.506 -5.241 O3' -19.434 -20.193 -8.147 4 G P -20.556 -19.092 -8.535 O3' -25.709 -19.760 -8.808 5 A P -26.856 -18.618 -8.777 O3' -32.202 -19.177 -5.673 6 C P -33.658 -18.458 -5.517 O3' -36.527 -15.140 -4.857 7 G P -36.932 -14.409 -3.455 O3' -35.118 -14.333 1.181 8 G P -35.098 -12.831 1.816 O3' -33.282 -11.182 5.939 9 U P -33.557 -9.610 6.266 O3' -30.297 -5.764 7.690 10 G P -30.509 -4.239 7.178 O3' -27.002 -0.632 4.005 11 U P -27.850 0.712 3.701 O3' -27.828 2.504 -1.432 12 A P -28.862 3.705 -1.060 O3' -33.234 0.830 -4.030 13 A P -33.225 -0.671 -3.426 O3' -31.697 -4.997 -5.862 14 A P -30.789 -6.140 -5.148 O3' -25.451 -8.378 -6.903 15 A P -24.202 -9.075 -6.132 O3' -18.988 -7.681 -5.922 16 A P -18.198 -8.591 -4.829 O3' -17.053 -7.639 0.359 17 U P -16.663 -8.944 1.239 O3' -18.979 -10.909 5.690 18 C P -18.902 -12.481 6.121 O3' -22.487 -15.162 9.181 19 U P -22.336 -16.758 9.443 O3' -26.067 -20.562 9.446 20 C P -25.671 -22.118 9.194 O3' -28.577 -25.501 6.157 21 G P -27.889 -26.892 5.684 O3' -28.324 -29.190 0.963 22 C P -27.338 -30.465 0.806 O3' -24.201 -31.722 -3.084 23 C P -22.978 -32.750 -2.815 O3' -17.194 -32.159 -3.544 1 23 + + c 2 22 + + c 3 21 + + c 4 20 + + c 5 19 - - c 7 18 + + c 8 17 W W c 9 16 - - c 10 15 S H t 9 17 ! ! ! 11 13 ! ! ! 11 14 ! ! ! 1 23 5 7 18 4 SG1 6 6 SG2 11 14 1 126.802 0.000 2 126.802 50.016 3 126.802 100.032 4 126.802 150.047 5 126.802 200.063 6 126.802 250.079 7 126.802 300.095 8 126.802 350.111 9 126.802 400.127 10 126.802 450.142 11 133.565 507.110 12 95.467 550.000 13 38.099 550.000 14 0.000 507.110 15 6.764 450.142 16 6.764 400.127 17 6.764 350.111 18 6.764 300.095 19 6.764 200.063 20 6.764 150.047 21 6.764 100.032 22 6.764 50.016 23 6.764 0.000