HEADER IMMUNE SYSTEM 10-MAR-08 3CHN TITLE Solution structure of human secretory IgA1 COMPND MOL_ID: 2; COMPND 2 MOLECULE: Ig alpha-1 chain C region; COMPND 3 CHAIN: A, B, D, C; EXPDTA SOLUTION SCATTERING DBREF 3CHN C 123 475 UNP P01876 IGHA1_HUMAN 1 353 SEQRES 1 C 108 ASN THR PHE ARG PRO GLU VAL HIS LEU LEU PRO PRO PRO SEQRES 2 C 108 SER GLU GLU LEU ALA LEU ASN GLU LEU VAL THR LEU THR SEQRES 3 C 108 CYS LEU ALA ARG GLY PHE SER PRO LYS ASP VAL LEU VAL SEQRES 4 C 108 ARG TRP LEU GLN GLY SER GLN GLU LEU PRO ARG GLU LYS SEQRES 5 C 108 TYR LEU THR TRP ALA SER ARG GLN GLU PRO SER GLN GLY SEQRES 6 C 108 THR THR THR PHE ALA VAL THR SER ILE LEU ARG VAL ALA SEQRES 7 C 108 ALA GLU ASP TRP LYS LYS GLY ASP THR PHE SER CYS MET SEQRES 8 C 108 VAL GLY HIS GLU ALA LEU PRO LEU ALA PHE THR GLN LYS SEQRES 9 C 108 THR ILE ASP ARG ATOM 1 CA ASN C 346 14.525 76.022 16.848 0.00 0.00 ATOM 2 CA THR C 347 16.505 72.726 17.458 0.00 0.00 ATOM 3 CA PHE C 348 16.256 69.257 15.689 0.00 0.00 ATOM 4 CA ARG C 349 18.055 65.942 16.666 0.00 0.00 ATOM 5 CA PRO C 350 20.673 64.742 14.038 0.00 0.00 ATOM 6 CA GLU C 351 19.978 61.312 12.476 0.00 0.00 ATOM 7 CA VAL C 352 23.448 59.623 12.143 0.00 0.00 ATOM 8 CA HIS C 353 23.707 56.666 9.655 0.00 0.00 ATOM 9 CA LEU C 354 27.139 55.068 8.913 0.00 0.00 ATOM 10 CA LEU C 355 27.597 53.765 5.340 0.00 0.00 ATOM 11 CA PRO C 356 30.252 51.115 4.389 0.00 0.00 ATOM 12 CA PRO C 357 32.179 51.415 1.043 0.00 0.00 ATOM 13 CA PRO C 358 30.660 50.482 -2.351 0.00 0.00 ATOM 14 CA SER C 359 31.582 47.013 -3.801 0.00 0.00 ATOM 15 CA GLU C 360 33.463 48.699 -6.745 0.00 0.00 ATOM 16 CA GLU C 361 35.672 50.810 -4.338 0.00 0.00 ATOM 17 CA LEU C 362 37.089 47.484 -2.949 0.00 0.00 ATOM 18 CA ALA C 363 38.795 47.188 -6.403 0.00 0.00 ATOM 19 CA LEU C 364 40.786 50.267 -5.100 0.00 0.00 ATOM 20 CA ASN C 365 43.626 49.980 -2.462 0.00 0.00 ATOM 21 CA GLU C 366 45.220 52.873 -0.397 0.00 0.00 ATOM 22 CA LEU C 367 41.930 54.548 0.759 0.00 0.00 ATOM 23 CA VAL C 368 38.518 52.888 1.529 0.00 0.00 ATOM 24 CA THR C 369 35.762 55.449 1.711 0.00 0.00 ATOM 25 CA LEU C 370 33.928 55.150 5.104 0.00 0.00 ATOM 26 CA THR C 371 30.955 57.548 5.054 0.00 0.00 ATOM 27 CA CYS C 372 28.683 58.854 7.828 0.00 0.00 ATOM 28 CA LEU C 373 25.535 60.854 6.952 0.00 0.00 ATOM 29 CA ALA C 374 24.309 63.341 9.620 0.00 0.00 ATOM 30 CA ARG C 375 20.848 64.510 8.423 0.00 0.00 ATOM 31 CA GLY C 376 17.706 66.418 9.586 0.00 0.00 ATOM 32 CA PHE C 377 19.632 68.556 12.154 0.00 0.00 ATOM 33 CA SER C 378 19.196 72.234 13.276 0.00 0.00 ATOM 34 CA PRO C 379 20.766 74.616 13.919 0.00 0.00 ATOM 35 CA LYS C 380 23.745 74.039 11.504 0.00 0.00 ATOM 36 CA ASP C 381 26.038 74.092 14.534 0.00 0.00 ATOM 37 CA VAL C 382 27.607 70.558 14.787 0.00 0.00 ATOM 38 CA LEU C 383 30.959 68.709 15.362 0.00 0.00 ATOM 39 CA VAL C 384 31.688 65.382 13.656 0.00 0.00 ATOM 40 CA ARG C 385 34.863 63.328 14.391 0.00 0.00 ATOM 41 CA TRP C 386 36.090 59.768 13.638 0.00 0.00 ATOM 42 CA LEU C 387 37.661 57.114 15.920 0.00 0.00 ATOM 43 CA GLN C 388 39.577 53.841 15.363 0.00 0.00 ATOM 44 CA GLY C 389 38.457 50.869 17.582 0.00 0.00 ATOM 45 CA SER C 390 41.536 48.720 16.645 0.00 0.00 ATOM 46 CA GLN C 391 44.113 51.149 18.252 0.00 0.00 ATOM 47 CA GLU C 392 41.717 52.911 20.768 0.00 0.00 ATOM 48 CA LEU C 393 42.659 56.293 19.165 0.00 0.00 ATOM 49 CA PRO C 394 41.201 59.227 17.125 0.00 0.00 ATOM 50 CA ARG C 395 41.728 59.076 13.315 0.00 0.00 ATOM 51 CA GLU C 396 43.476 61.434 10.848 0.00 0.00 ATOM 52 CA LYS C 397 42.494 60.866 7.191 0.00 0.00 ATOM 53 CA TYR C 398 38.952 62.299 7.243 0.00 0.00 ATOM 54 CA LEU C 399 37.165 65.274 5.615 0.00 0.00 ATOM 55 CA THR C 400 33.683 66.788 6.412 0.00 0.00 ATOM 56 CA TRP C 401 31.614 68.819 3.830 0.00 0.00 ATOM 57 CA ALA C 402 28.342 70.928 4.255 0.00 0.00 ATOM 58 CA SER C 403 24.644 71.347 3.081 0.00 0.00 ATOM 59 CA ARG C 404 21.950 73.735 4.539 0.00 0.00 ATOM 60 CA GLN C 405 18.568 72.620 3.004 0.00 0.00 ATOM 61 CA GLU C 406 16.083 75.482 2.169 0.00 0.00 ATOM 62 CA PRO C 407 13.557 75.404 -0.786 0.00 0.00 ATOM 63 CA SER C 408 10.371 77.590 -1.281 0.00 0.00 ATOM 64 CA GLN C 409 8.397 75.566 1.377 0.00 0.00 ATOM 65 CA GLY C 410 8.474 75.451 5.243 0.00 0.00 ATOM 66 CA THR C 411 10.962 72.493 5.173 0.00 0.00 ATOM 67 CA THR C 412 14.426 73.809 6.353 0.00 0.00 ATOM 68 CA THR C 413 17.000 71.551 8.249 0.00 0.00 ATOM 69 CA PHE C 414 20.710 70.613 7.438 0.00 0.00 ATOM 70 CA ALA C 415 22.648 67.572 6.156 0.00 0.00 ATOM 71 CA VAL C 416 26.412 66.746 5.987 0.00 0.00 ATOM 72 CA THR C 417 28.484 63.747 4.869 0.00 0.00 ATOM 73 CA SER C 418 31.845 62.954 6.570 0.00 0.00 ATOM 74 CA ILE C 419 34.433 60.860 4.667 0.00 0.00 ATOM 75 CA LEU C 420 37.029 58.702 6.566 0.00 0.00 ATOM 76 CA ARG C 421 39.528 57.189 4.108 0.00 0.00 ATOM 77 CA VAL C 422 41.267 53.893 5.246 0.00 0.00 ATOM 78 CA ALA C 423 43.562 51.160 3.816 0.00 0.00 ATOM 79 CA ALA C 424 41.426 48.349 2.177 0.00 0.00 ATOM 80 CA GLU C 425 43.194 45.807 4.488 0.00 0.00 ATOM 81 CA ASP C 426 42.213 47.300 7.953 0.00 0.00 ATOM 82 CA TRP C 427 38.481 47.339 7.009 0.00 0.00 ATOM 83 CA LYS C 428 38.880 43.604 5.991 0.00 0.00 ATOM 84 CA LYS C 429 40.928 42.890 9.203 0.00 0.00 ATOM 85 CA GLY C 430 37.491 43.484 10.875 0.00 0.00 ATOM 86 CA ASP C 431 38.195 46.904 12.420 0.00 0.00 ATOM 87 CA THR C 432 35.407 48.979 14.018 0.00 0.00 ATOM 88 CA PHE C 433 35.463 52.691 13.026 0.00 0.00 ATOM 89 CA SER C 434 33.018 55.100 14.756 0.00 0.00 ATOM 90 CA CYS C 435 31.628 58.471 13.657 0.00 0.00 ATOM 91 CA MET C 436 31.049 60.695 16.763 0.00 0.00 ATOM 92 CA VAL C 437 28.491 63.536 16.317 0.00 0.00 ATOM 93 CA GLY C 438 28.106 66.400 18.854 0.00 0.00 ATOM 94 CA HIS C 439 25.027 68.639 18.596 0.00 0.00 ATOM 95 CA GLU C 440 22.719 70.856 20.796 0.00 0.00 ATOM 96 CA ALA C 441 19.742 68.397 20.427 0.00 0.00 ATOM 97 CA LEU C 442 21.629 65.083 21.058 0.00 0.00 ATOM 98 CA PRO C 443 20.809 63.190 24.366 0.00 0.00 ATOM 99 CA LEU C 444 24.140 63.857 26.199 0.00 0.00 ATOM 100 CA ALA C 445 25.163 66.429 23.485 0.00 0.00 ATOM 101 CA PHE C 446 26.967 63.400 21.977 0.00 0.00 ATOM 102 CA THR C 447 26.101 60.295 19.927 0.00 0.00 ATOM 103 CA GLN C 448 28.405 57.771 18.207 0.00 0.00 ATOM 104 CA LYS C 449 27.398 55.320 15.401 0.00 0.00 ATOM 105 CA THR C 450 29.802 52.470 14.446 0.00 0.00 ATOM 106 CA ILE C 451 30.994 50.758 11.172 0.00 0.00 ATOM 107 CA ASP C 452 32.783 47.378 10.738 0.00 0.00 ATOM 108 CA ARG C 453 33.204 44.617 8.048 0.00 0.00 TER