>>6TXA:HELIX   46 AF1 ASP B  309  GLY B  324  1                                  16    
DVDKWDYFARDCHHLG
Search OCA for entries with sequence similar to this one (with E=10)

HELIX 46 AF1 ASP B 309 GLY B 324 1 16 ATOM 5357 N ASP B 309 80.310 70.691 -84.557 1.00 27.52 N ANISOU 5357 N ASP B 309 3296 3602 3559 405 1133 583 N ATOM 5358 CA ASP B 309 80.932 69.467 -85.086 1.00 27.20 C ANISOU 5358 CA ASP B 309 3250 3563 3521 396 1103 573 C ATOM 5359 C ASP B 309 80.667 68.240 -84.198 1.00 25.13 C ANISOU 5359 C ASP B 309 2962 3325 3260 364 1042 562 C ATOM 5360 O ASP B 309 80.164 68.356 -83.079 1.00 24.44 O ANISOU 5360 O ASP B 309 2857 3252 3176 344 1026 560 O ATOM 5361 CB ASP B 309 82.445 69.679 -85.322 1.00 28.46 C ANISOU 5361 CB ASP B 309 3413 3687 3712 386 1137 556 C ATOM 5362 CG ASP B 309 83.205 70.229 -84.073 1.00 29.55 C ANISOU 5362 CG ASP B 309 3533 3806 3887 350 1154 536 C ATOM 5363 OD1 ASP B 309 83.208 69.578 -83.000 1.00 30.20 O ANISOU 5363 OD1 ASP B 309 3592 3903 3981 320 1116 523 O ATOM 5364 OD2 ASP B 309 83.857 71.300 -84.164 1.00 30.39 O ANISOU 5364 OD2 ASP B 309 3651 3883 4011 351 1206 533 O ATOM 5365 N VAL B 310 81.001 67.062 -84.698 1.00 23.60 N ANISOU 5365 N VAL B 310 2768 3137 3062 360 1009 555 N ATOM 5366 CA VAL B 310 80.711 65.843 -83.959 1.00 22.80 C ANISOU 5366 CA VAL B 310 2648 3056 2958 331 952 547 C ATOM 5367 C VAL B 310 81.718 65.572 -82.823 1.00 22.66 C ANISOU 5367 C VAL B 310 2612 3023 2975 295 944 524 C ATOM 5368 O VAL B 310 81.414 64.776 -81.952 1.00 22.66 O ANISOU 5368 O VAL B 310 2596 3038 2974 270 901 519 O ATOM 5369 CB VAL B 310 80.528 64.603 -84.888 1.00 22.41 C ANISOU 5369 CB VAL B 310 2608 3019 2886 341 914 549 C ATOM 5370 CG1 VAL B 310 79.542 64.890 -86.001 1.00 22.14 C ANISOU 5370 CG1 VAL B 310 2590 3004 2817 377 922 569 C ATOM 5371 CG2 VAL B 310 81.825 64.120 -85.505 1.00 22.58 C ANISOU 5371 CG2 VAL B 310 2638 3016 2924 344 921 534 C ATOM 5372 N ASP B 311 82.897 66.211 -82.830 1.00 22.68 N ANISOU 5372 N ASP B 311 2615 2997 3005 293 983 511 N ATOM 5373 CA ASP B 311 83.825 66.150 -81.688 1.00 22.82 C ANISOU 5373 CA ASP B 311 2611 3003 3055 261 981 488 C ATOM 5374 C ASP B 311 83.028 66.592 -80.454 1.00 23.31 C ANISOU 5374 C ASP B 311 2658 3081 3118 243 972 491 C ATOM 5375 O ASP B 311 82.951 65.873 -79.455 1.00 23.26 O ANISOU 5375 O ASP B 311 2633 3087 3116 217 934 483 O ATOM 5376 CB ASP B 311 85.049 67.056 -81.902 1.00 23.01 C ANISOU 5376 CB ASP B 311 2637 2999 3106 262 1034 474 C ATOM 5377 CG ASP B 311 86.177 66.819 -80.898 1.00 23.28 C ANISOU 5377 CG ASP B 311 2647 3024 3171 231 1029 446 C ATOM 5378 OD1 ASP B 311 86.461 65.668 -80.471 1.00 22.64 O ANISOU 5378 OD1 ASP B 311 2555 2955 3092 217 985 435 O ATOM 5379 OD2 ASP B 311 86.826 67.820 -80.569 1.00 24.35 O ANISOU 5379 OD2 ASP B 311 2778 3143 3330 222 1071 435 O ATOM 5380 N LYS B 312 82.375 67.749 -80.566 1.00 23.94 N ANISOU 5380 N LYS B 312 2746 3159 3189 260 1006 506 N ATOM 5381 CA LYS B 312 81.559 68.297 -79.474 1.00 23.60 C ANISOU 5381 CA LYS B 312 2690 3131 3144 248 1002 510 C ATOM 5382 C LYS B 312 80.479 67.338 -79.054 1.00 23.00 C ANISOU 5382 C LYS B 312 2603 3091 3044 239 948 520 C ATOM 5383 O LYS B 312 80.284 67.111 -77.859 1.00 23.85 O ANISOU 5383 O LYS B 312 2690 3211 3158 212 924 513 O ATOM 5384 CB LYS B 312 80.933 69.657 -79.834 1.00 24.59 C ANISOU 5384 CB LYS B 312 2832 3250 3258 275 1047 526 C ATOM 5385 CG LYS B 312 81.867 70.840 -79.567 1.00 25.41 C ANISOU 5385 CG LYS B 312 2942 3320 3392 270 1100 514 C ATOM 5386 CD LYS B 312 81.272 72.171 -80.021 1.00 26.12 C ANISOU 5386 CD LYS B 312 3056 3398 3469 300 1147 531 C ATOM 5387 CE LYS B 312 82.295 73.307 -80.084 1.00 26.28 C ANISOU 5387 CE LYS B 312 3090 3377 3517 296 1205 520 C ATOM 5388 NZ LYS B 312 83.348 73.116 -81.111 1.00 26.27 N ANISOU 5388 NZ LYS B 312 3100 3353 3526 301 1228 514 N ATOM 5389 N TRP B 313 79.787 66.763 -80.036 1.00 22.02 N ANISOU 5389 N TRP B 313 2491 2983 2890 258 929 535 N ATOM 5390 CA TRP B 313 78.602 65.985 -79.729 1.00 21.41 C ANISOU 5390 CA TRP B 313 2405 2942 2786 250 883 546 C ATOM 5391 C TRP B 313 78.962 64.762 -78.910 1.00 21.74 C ANISOU 5391 C TRP B 313 2432 2988 2838 214 837 532 C ATOM 5392 O TRP B 313 78.248 64.420 -77.948 1.00 21.73 O ANISOU 5392 O TRP B 313 2414 3011 2829 192 806 535 O ATOM 5393 CB TRP B 313 77.839 65.589 -80.988 1.00 20.64 C ANISOU 5393 CB TRP B 313 2323 2862 2654 277 872 562 C ATOM 5394 CG TRP B 313 77.349 66.738 -81.802 1.00 20.28 C ANISOU 5394 CG TRP B 313 2294 2818 2593 316 914 578 C ATOM 5395 CD1 TRP B 313 77.277 68.061 -81.432 1.00 20.13 C ANISOU 5395 CD1 TRP B 313 2278 2789 2581 328 956 582 C ATOM 5396 CD2 TRP B 313 76.848 66.662 -83.128 1.00 20.09 C ANISOU 5396 CD2 TRP B 313 2288 2804 2539 350 918 592 C ATOM 5397 NE1 TRP B 313 76.774 68.810 -82.464 1.00 20.33 N ANISOU 5397 NE1 TRP B 313 2324 2815 2582 370 986 599 N ATOM 5398 CE2 TRP B 313 76.504 67.976 -83.517 1.00 20.40 C ANISOU 5398 CE2 TRP B 313 2342 2840 2569 385 964 605 C ATOM 5399 CE3 TRP B 313 76.645 65.607 -84.028 1.00 19.88 C ANISOU 5399 CE3 TRP B 313 2269 2792 2492 357 887 594 C ATOM 5400 CZ2 TRP B 313 76.012 68.267 -84.788 1.00 20.59 C ANISOU 5400 CZ2 TRP B 313 2386 2872 2564 427 980 621 C ATOM 5401 CZ3 TRP B 313 76.123 65.894 -85.287 1.00 20.07 C ANISOU 5401 CZ3 TRP B 313 2310 2826 2487 397 902 608 C ATOM 5402 CH2 TRP B 313 75.798 67.207 -85.647 1.00 20.44 C ANISOU 5402 CH2 TRP B 313 2370 2870 2524 432 948 622 C ATOM 5403 N ASP B 314 80.077 64.133 -79.265 1.00 22.40 N ANISOU 5403 N ASP B 314 2521 3048 2938 210 833 517 N ATOM 5404 CA ASP B 314 80.513 62.965 -78.538 1.00 23.10 C ANISOU 5404 CA ASP B 314 2601 3138 3037 181 791 504 C ATOM 5405 C ASP B 314 80.920 63.353 -77.109 1.00 23.17 C ANISOU 5405 C ASP B 314 2588 3145 3071 156 794 491 C ATOM 5406 O ASP B 314 80.448 62.741 -76.150 1.00 23.82 O ANISOU 5406 O ASP B 314 2657 3245 3148 131 758 491 O ATOM 5407 CB ASP B 314 81.701 62.280 -79.182 1.00 23.91 C ANISOU 5407 CB ASP B 314 2715 3218 3153 186 788 489 C ATOM 5408 CG ASP B 314 82.157 61.074 -78.388 1.00 24.48 C ANISOU 5408 CG ASP B 314 2779 3288 3231 160 744 476 C ATOM 5409 OD1 ASP B 314 82.789 61.223 -77.254 1.00 25.38 O ANISOU 5409 OD1 ASP B 314 2876 3398 3369 140 746 461 O ATOM 5410 OD2 ASP B 314 81.916 60.018 -78.867 1.00 24.90 O ANISOU 5410 OD2 ASP B 314 2845 3346 3267 160 710 479 O ATOM 5411 N TYR B 315 81.812 64.329 -76.958 1.00 22.71 N ANISOU 5411 N TYR B 315 2525 3064 3038 160 837 479 N ATOM 5412 CA TYR B 315 82.333 64.606 -75.619 1.00 22.26 C ANISOU 5412 CA TYR B 315 2447 3005 3006 135 839 462 C ATOM 5413 C TYR B 315 81.285 65.183 -74.663 1.00 22.98 C ANISOU 5413 C TYR B 315 2524 3118 3087 126 835 472 C ATOM 5414 O TYR B 315 81.388 64.990 -73.456 1.00 23.48 O ANISOU 5414 O TYR B 315 2569 3190 3162 102 817 462 O ATOM 5415 CB TYR B 315 83.627 65.426 -75.627 1.00 21.66 C ANISOU 5415 CB TYR B 315 2366 2901 2960 136 883 442 C ATOM 5416 CG TYR B 315 83.552 66.935 -75.769 1.00 21.52 C ANISOU 5416 CG TYR B 315 2353 2870 2950 148 937 445 C ATOM 5417 CD1 TYR B 315 83.082 67.743 -74.730 1.00 21.46 C ANISOU 5417 CD1 TYR B 315 2333 2870 2949 137 947 444 C ATOM 5418 CD2 TYR B 315 84.069 67.573 -76.893 1.00 21.67 C ANISOU 5418 CD2 TYR B 315 2391 2867 2974 170 979 447 C ATOM 5419 CE1 TYR B 315 83.071 69.134 -74.843 1.00 21.59 C ANISOU 5419 CE1 TYR B 315 2358 2870 2973 149 997 446 C ATOM 5420 CE2 TYR B 315 84.068 68.951 -77.017 1.00 21.84 C ANISOU 5420 CE2 TYR B 315 2422 2871 3004 180 1030 450 C ATOM 5421 CZ TYR B 315 83.566 69.726 -76.009 1.00 21.89 C ANISOU 5421 CZ TYR B 315 2418 2882 3014 170 1039 449 C ATOM 5422 OH TYR B 315 83.568 71.089 -76.159 1.00 22.34 O ANISOU 5422 OH TYR B 315 2489 2919 3078 181 1090 452 O ATOM 5423 N PHE B 316 80.269 65.874 -75.176 1.00 23.84 N ANISOU 5423 N PHE B 316 2643 3239 3176 146 852 491 N ATOM 5424 CA PHE B 316 79.161 66.283 -74.312 1.00 24.11 C ANISOU 5424 CA PHE B 316 2663 3300 3195 140 843 502 C ATOM 5425 C PHE B 316 78.551 65.037 -73.682 1.00 23.06 C ANISOU 5425 C PHE B 316 2518 3195 3047 115 787 506 C ATOM 5426 O PHE B 316 78.508 64.901 -72.460 1.00 22.33 O ANISOU 5426 O PHE B 316 2407 3114 2963 91 770 500 O ATOM 5427 CB PHE B 316 78.080 67.020 -75.098 1.00 25.67 C ANISOU 5427 CB PHE B 316 2874 3513 3366 170 862 524 C ATOM 5428 CG PHE B 316 78.445 68.426 -75.519 1.00 27.22 C ANISOU 5428 CG PHE B 316 3084 3683 3573 195 919 523 C ATOM 5429 CD1 PHE B 316 79.687 68.997 -75.269 1.00 27.69 C ANISOU 5429 CD1 PHE B 316 3144 3709 3667 186 953 504 C ATOM 5430 CD2 PHE B 316 77.519 69.161 -76.236 1.00 28.51 C ANISOU 5430 CD2 PHE B 316 3263 3857 3711 228 940 543 C ATOM 5431 CE1 PHE B 316 79.973 70.276 -75.704 1.00 28.57 C ANISOU 5431 CE1 PHE B 316 3272 3794 3787 206 1006 505 C ATOM 5432 CE2 PHE B 316 77.801 70.425 -76.677 1.00 28.97 C ANISOU 5432 CE2 PHE B 316 3340 3890 3777 252 993 545 C ATOM 5433 CZ PHE B 316 79.026 70.989 -76.411 1.00 29.16 C ANISOU 5433 CZ PHE B 316 3365 3876 3835 240 1027 526 C ATOM 5434 N ALA B 317 78.115 64.126 -74.543 1.00 22.62 N ANISOU 5434 N ALA B 317 2475 3149 2969 120 761 517 N ATOM 5435 CA ALA B 317 77.462 62.905 -74.121 1.00 22.53 C ANISOU 5435 CA ALA B 317 2458 3162 2939 96 710 523 C ATOM 5436 C ALA B 317 78.372 62.068 -73.227 1.00 21.85 C ANISOU 5436 C ALA B 317 2364 3062 2874 69 685 506 C ATOM 5437 O ALA B 317 77.938 61.578 -72.187 1.00 22.62 O ANISOU 5437 O ALA B 317 2449 3179 2967 43 655 507 O ATOM 5438 CB ALA B 317 77.044 62.098 -75.345 1.00 22.66 C ANISOU 5438 CB ALA B 317 2493 3184 2931 108 690 533 C ATOM 5439 N ARG B 318 79.624 61.931 -73.632 1.00 20.80 N ANISOU 5439 N ARG B 318 2241 2899 2763 76 698 490 N ATOM 5440 CA ARG B 318 80.553 61.057 -72.950 1.00 20.24 C ANISOU 5440 CA ARG B 318 2166 2816 2709 56 673 473 C ATOM 5441 C ARG B 318 81.007 61.627 -71.620 1.00 20.31 C ANISOU 5441 C ARG B 318 2151 2825 2740 41 684 459 C ATOM 5442 O ARG B 318 81.041 60.906 -70.633 1.00 20.01 O ANISOU 5442 O ARG B 318 2104 2796 2703 19 651 454 O ATOM 5443 CB ARG B 318 81.792 60.813 -73.806 1.00 19.90 C ANISOU 5443 CB ARG B 318 2136 2744 2681 72 687 458 C ATOM 5444 CG ARG B 318 82.683 59.684 -73.267 1.00 19.18 C ANISOU 5444 CG ARG B 318 2044 2642 2599 58 654 442 C ATOM 5445 CD ARG B 318 83.771 59.336 -74.283 1.00 18.39 C ANISOU 5445 CD ARG B 318 1960 2519 2508 78 664 429 C ATOM 5446 NE ARG B 318 83.144 58.962 -75.546 1.00 17.78 N ANISOU 5446 NE ARG B 318 1904 2442 2407 94 657 444 N ATOM 5447 CZ ARG B 318 82.573 57.797 -75.799 1.00 17.16 C ANISOU 5447 CZ ARG B 318 1843 2370 2307 87 615 453 C ATOM 5448 NH1 ARG B 318 82.583 56.824 -74.863 1.00 16.94 N ANISOU 5448 NH1 ARG B 318 1814 2344 2276 64 575 449 N ATOM 5449 NH2 ARG B 318 82.006 57.611 -76.989 1.00 16.94 N ANISOU 5449 NH2 ARG B 318 1832 2344 2257 104 614 465 N ATOM 5450 N ASP B 319 81.403 62.896 -71.614 1.00 20.66 N ANISOU 5450 N ASP B 319 2188 2858 2802 52 729 451 N ATOM 5451 CA ASP B 319 81.922 63.517 -70.397 1.00 21.10 C ANISOU 5451 CA ASP B 319 2221 2913 2880 38 742 434 C ATOM 5452 C ASP B 319 80.812 63.547 -69.362 1.00 21.48 C ANISOU 5452 C ASP B 319 2255 2992 2913 22 720 447 C ATOM 5453 O ASP B 319 81.034 63.160 -68.215 1.00 21.70 O ANISOU 5453 O ASP B 319 2267 3028 2948 2 699 437 O ATOM 5454 CB ASP B 319 82.513 64.927 -70.623 1.00 21.43 C ANISOU 5454 CB ASP B 319 2261 2936 2943 51 797 424 C ATOM 5455 CG ASP B 319 83.736 64.929 -71.568 1.00 21.76 C ANISOU 5455 CG ASP B 319 2314 2950 3003 63 821 409 C ATOM 5456 OD1 ASP B 319 84.290 63.833 -71.873 1.00 22.25 O ANISOU 5456 OD1 ASP B 319 2382 3008 3063 62 794 403 O ATOM 5457 OD2 ASP B 319 84.127 66.049 -72.008 1.00 21.58 O ANISOU 5457 OD2 ASP B 319 2296 2909 2993 75 869 404 O ATOM 5458 N CYS B 320 79.607 63.940 -69.776 1.00 21.84 N ANISOU 5458 N CYS B 320 2306 3056 2936 33 724 468 N ATOM 5459 CA CYS B 320 78.443 63.902 -68.873 1.00 22.14 C ANISOU 5459 CA CYS B 320 2329 3128 2954 18 701 481 C ATOM 5460 C CYS B 320 78.213 62.522 -68.235 1.00 21.61 C ANISOU 5460 C CYS B 320 2257 3076 2875 -8 650 484 C ATOM 5461 O CYS B 320 77.979 62.405 -67.029 1.00 21.85 O ANISOU 5461 O CYS B 320 2270 3125 2906 -28 633 482 O ATOM 5462 CB CYS B 320 77.199 64.357 -69.610 1.00 22.68 C ANISOU 5462 CB CYS B 320 2405 3218 2994 37 710 503 C ATOM 5463 SG CYS B 320 77.191 66.137 -69.785 1.00 24.97 S ANISOU 5463 SG CYS B 320 2696 3497 3293 65 767 502 S ATOM 5464 N HIS B 321 78.296 61.487 -69.046 1.00 21.08 N ANISOU 5464 N HIS B 321 2209 3001 2798 -8 627 489 N ATOM 5465 CA HIS B 321 78.049 60.129 -68.576 1.00 20.71 C ANISOU 5465 CA HIS B 321 2166 2965 2738 -33 579 493 C ATOM 5466 C HIS B 321 78.987 59.766 -67.438 1.00 21.32 C ANISOU 5466 C HIS B 321 2233 3032 2836 -49 567 476 C ATOM 5467 O HIS B 321 78.557 59.208 -66.436 1.00 21.82 O ANISOU 5467 O HIS B 321 2287 3113 2890 -73 538 481 O ATOM 5468 CB HIS B 321 78.222 59.171 -69.749 1.00 20.09 C ANISOU 5468 CB HIS B 321 2113 2870 2648 -26 562 496 C ATOM 5469 CG HIS B 321 78.023 57.730 -69.423 1.00 19.71 C ANISOU 5469 CG HIS B 321 2077 2825 2587 -51 514 501 C ATOM 5470 ND1 HIS B 321 76.784 57.140 -69.355 1.00 19.72 N ANISOU 5470 ND1 HIS B 321 2080 2854 2559 -71 485 519 N ATOM 5471 CD2 HIS B 321 78.911 56.733 -69.224 1.00 19.60 C ANISOU 5471 CD2 HIS B 321 2076 2789 2582 -59 491 489 C ATOM 5472 CE1 HIS B 321 76.929 55.843 -69.108 1.00 19.78 C ANISOU 5472 CE1 HIS B 321 2103 2852 2559 -92 447 519 C ATOM 5473 NE2 HIS B 321 78.217 55.572 -69.020 1.00 19.63 N ANISOU 5473 NE2 HIS B 321 2093 2803 2563 -83 449 501 N ATOM 5474 N HIS B 322 80.255 60.113 -67.609 1.00 22.42 N ANISOU 5474 N HIS B 322 2372 3144 3001 -36 591 455 N ATOM 5475 CA HIS B 322 81.309 59.781 -66.647 1.00 23.35 C ANISOU 5475 CA HIS B 322 2479 3253 3139 -46 582 435 C ATOM 5476 C HIS B 322 81.397 60.827 -65.506 1.00 22.56 C ANISOU 5476 C HIS B 322 2351 3164 3055 -52 603 424 C ATOM 5477 O HIS B 322 81.703 60.474 -64.370 1.00 21.57 O ANISOU 5477 O HIS B 322 2213 3048 2935 -67 584 415 O ATOM 5478 CB HIS B 322 82.682 59.574 -67.365 1.00 24.49 C ANISOU 5478 CB HIS B 322 2634 3367 3302 -30 594 415 C ATOM 5479 CG HIS B 322 82.739 58.344 -68.227 1.00 26.19 C ANISOU 5479 CG HIS B 322 2876 3571 3502 -26 565 421 C ATOM 5480 ND1 HIS B 322 82.422 58.353 -69.573 1.00 28.00 N ANISOU 5480 ND1 HIS B 322 3125 3792 3721 -9 575 432 N ATOM 5481 CD2 HIS B 322 83.059 57.058 -67.927 1.00 27.83 C ANISOU 5481 CD2 HIS B 322 3097 3773 3703 -35 526 418 C ATOM 5482 CE1 HIS B 322 82.546 57.126 -70.069 1.00 30.24 C ANISOU 5482 CE1 HIS B 322 3431 4066 3992 -9 543 434 C ATOM 5483 NE2 HIS B 322 82.917 56.317 -69.083 1.00 29.98 N ANISOU 5483 NE2 HIS B 322 3396 4032 3960 -25 512 427 N ATOM 5484 N LEU B 323 81.128 62.100 -65.796 1.00 22.18 N ANISOU 5484 N LEU B 323 2297 3117 3013 -40 642 425 N ATOM 5485 CA LEU B 323 81.240 63.143 -64.772 1.00 22.52 C ANISOU 5485 CA LEU B 323 2316 3167 3070 -44 665 413 C ATOM 5486 C LEU B 323 80.190 62.987 -63.684 1.00 24.31 C ANISOU 5486 C LEU B 323 2529 3427 3280 -61 639 426 C ATOM 5487 O LEU B 323 80.481 63.158 -62.471 1.00 25.83 O ANISOU 5487 O LEU B 323 2701 3630 3483 -74 635 413 O ATOM 5488 CB LEU B 323 81.102 64.536 -65.374 1.00 21.44 C ANISOU 5488 CB LEU B 323 2182 3020 2941 -25 713 414 C ATOM 5489 CG LEU B 323 82.295 65.079 -66.130 1.00 20.81 C ANISOU 5489 CG LEU B 323 2111 2909 2887 -12 750 395 C ATOM 5490 CD1 LEU B 323 81.905 66.320 -66.902 1.00 20.81 C ANISOU 5490 CD1 LEU B 323 2121 2898 2885 7 794 403 C ATOM 5491 CD2 LEU B 323 83.452 65.379 -65.182 1.00 20.40 C ANISOU 5491 CD2 LEU B 323 2037 2849 2862 -24 761 365 C ATOM 5492 N GLY B 324 78.982 62.633 -64.128 1.00 25.11 N ATOM 5493 CA GLY B 324 77.809 62.665 -63.284 1.00 25.66 C ATOM 5494 C GLY B 324 77.077 63.982 -63.396 1.00 26.50 C ATOM 5495 O GLY B 324 76.580 64.513 -62.420 1.00 28.18 O