1 17 26 27 28 29 30 31 32 33 34 35 41 42 43 44 45 46 47 GCCAAUGAGG CCGAGGC LOOP1 11 10 Crystallography ? ? Angstroms 1 G O3' 27.526 42.283 13.660 2 C P 29.056 42.757 13.595 O3' 31.669 42.331 17.865 3 C P 33.197 42.689 17.512 O3' 37.269 40.110 19.835 4 A P 38.534 40.754 19.095 O3' 42.488 37.833 17.179 5 A P 43.336 38.969 16.405 O3' 48.144 37.206 14.217 6 U P 49.057 38.512 13.985 O3' 47.410 39.696 19.410 7 G P 47.277 38.350 20.264 O3' 43.642 33.749 19.832 8 A P 42.392 34.145 20.731 O3' 37.928 31.409 19.173 9 G P 37.409 31.413 20.678 O3' 37.679 25.560 21.550 10 G P 36.823 24.667 22.565 O3' 38.700 21.111 24.075 11 C P 54.537 26.871 20.874 O3' 54.364 22.358 18.202 12 C P 53.808 22.569 16.713 O3' 49.543 20.869 13.733 13 G P 49.783 21.453 12.255 O3' 45.307 25.282 11.544 14 A P 44.672 25.683 10.120 O3' 39.532 27.674 9.644 15 G P 38.639 26.389 9.330 O3' 35.808 25.712 14.361 16 G P 34.239 25.680 14.686 O3' 32.377 26.534 19.366 17 C P 30.919 25.940 19.012 O3' 26.952 28.016 20.409 5 syn 1 17 + + c 2 16 + + c 3 15 + + c 7 14 S H t 8 13 H S t 9 12 + + c 10 11 + + c 9 13 ! ! ! 4 14 ! ! ! 4 5 ! ! ! 1 17 3 7 14 4 SG1 4 6 1 423.054 217.979 2 376.308 165.084 3 329.562 112.190 4 301.514 80.454 5 273.467 48.717 6 245.419 16.980 7 0.000 111.681 8 0.000 182.272 9 0.000 252.862 10 0.000 323.452 11 169.417 323.452 12 169.417 252.862 13 169.417 182.272 14 169.417 111.681 15 456.508 0.000 16 503.254 52.894 17 550.000 105.789