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 115 THR PRO SER PRO SER THR PRO PRO THR PRO SER PRO SER SEQRES 2 C 115 CYS CYS HIS PRO ARG LEU SER LEU HIS ARG PRO ALA LEU SEQRES 3 C 115 GLU ASP LEU LEU LEU GLY SER GLU ALA ASN LEU THR CYS SEQRES 4 C 115 THR LEU THR GLY LEU ARG ASP ALA SER GLY VAL THR PHE SEQRES 5 C 115 THR TRP THR PRO SER SER GLY LYS SER ALA VAL GLN GLY SEQRES 6 C 115 PRO PRO GLU ARG ASP LEU CYS GLY CYS TYR SER VAL SER SEQRES 7 C 115 SER VAL LEU PRO GLY CYS ALA GLU PRO TRP ASN HIS GLY SEQRES 8 C 115 LYS THR PHE THR CYS THR ALA ALA TYR PRO GLU SER LYS SEQRES 9 C 115 THR PRO LEU THR ALA THR LEU SER LYS SER GLY ATOM 1 CA THR C 231 62.710 140.538 -7.744 1.00 0.00 ATOM 2 CA PRO C 232 61.834 136.799 -8.657 1.00 0.00 ATOM 3 CA SER C 233 58.968 135.231 -6.522 1.00 0.00 ATOM 4 CA PRO C 234 60.333 132.215 -4.429 1.00 0.00 ATOM 5 CA SER C 235 56.784 130.827 -3.585 1.00 0.00 ATOM 6 CA THR C 236 55.649 127.184 -2.775 1.00 0.00 ATOM 7 CA PRO C 237 51.907 126.602 -2.003 1.00 0.00 ATOM 8 CA PRO C 238 51.278 123.284 0.210 1.00 0.00 ATOM 9 CA THR C 239 47.396 122.147 -0.182 1.00 0.00 ATOM 10 CA PRO C 240 46.152 118.704 1.494 1.00 0.00 ATOM 11 CA SER C 241 42.733 116.672 0.662 1.00 0.00 ATOM 12 CA PRO C 242 39.336 115.209 2.009 1.00 0.00 ATOM 13 CA SER C 243 37.474 111.846 1.890 1.00 0.00 ATOM 14 CA CYS C 244 33.989 110.408 2.503 1.00 0.00 ATOM 15 CA CYS C 245 31.683 110.465 5.758 1.00 0.00 ATOM 16 CA HIS C 246 28.719 108.061 5.777 1.00 0.00 ATOM 17 CA PRO C 247 26.905 106.730 9.134 0.00 0.00 ATOM 18 CA ARG C 248 26.471 102.885 8.840 0.00 0.00 ATOM 19 CA LEU C 249 26.358 100.473 11.894 0.00 0.00 ATOM 20 CA SER C 250 27.523 96.846 11.152 0.00 0.00 ATOM 21 CA LEU C 251 27.806 93.750 13.454 0.00 0.00 ATOM 22 CA HIS C 252 30.310 91.034 12.321 0.00 0.00 ATOM 23 CA ARG C 253 29.648 87.663 14.144 0.00 0.00 ATOM 24 CA PRO C 254 32.321 85.295 15.707 0.00 0.00 ATOM 25 CA ALA C 255 33.819 82.515 13.426 0.00 0.00 ATOM 26 CA LEU C 256 32.603 78.843 13.886 0.00 0.00 ATOM 27 CA GLU C 257 36.072 77.094 13.883 0.00 0.00 ATOM 28 CA ASP C 258 37.670 79.500 16.497 0.00 0.00 ATOM 29 CA LEU C 259 34.683 79.397 18.971 0.00 0.00 ATOM 30 CA LEU C 260 34.546 75.514 18.776 0.00 0.00 ATOM 31 CA LEU C 261 38.371 74.842 18.935 0.00 0.00 ATOM 32 CA GLY C 262 39.475 76.514 22.251 0.00 0.00 ATOM 33 CA SER C 263 36.551 78.962 23.091 0.00 0.00 ATOM 34 CA GLU C 264 37.842 81.930 20.952 0.00 0.00 ATOM 35 CA ALA C 265 34.865 84.173 19.910 0.00 0.00 ATOM 36 CA ASN C 266 34.667 87.993 19.449 0.00 0.00 ATOM 37 CA LEU C 267 31.462 89.801 18.372 0.00 0.00 ATOM 38 CA THR C 268 32.660 92.892 16.508 0.00 0.00 ATOM 39 CA CYS C 269 30.830 96.263 16.305 0.00 0.00 ATOM 40 CA THR C 270 31.750 98.619 13.438 0.00 0.00 ATOM 41 CA LEU C 271 30.402 102.223 13.035 0.00 0.00 ATOM 42 CA THR C 272 31.062 103.364 9.430 0.00 0.00 ATOM 43 CA GLY C 273 29.825 106.847 8.267 0.00 0.00 ATOM 44 CA LEU C 274 30.381 109.168 11.330 0.00 0.00 ATOM 45 CA ARG C 275 31.167 112.613 9.650 0.00 0.00 ATOM 46 CA ASP C 276 33.854 115.249 10.693 0.00 0.00 ATOM 47 CA ALA C 277 34.587 116.441 14.357 0.00 0.00 ATOM 48 CA SER C 278 33.046 113.411 16.098 0.00 0.00 ATOM 49 CA GLY C 279 33.132 110.491 18.650 0.00 0.00 ATOM 50 CA VAL C 280 31.107 107.251 19.253 0.00 0.00 ATOM 51 CA THR C 281 29.925 105.878 22.682 0.00 0.00 ATOM 52 CA PHE C 282 29.402 102.091 22.883 0.00 0.00 ATOM 53 CA THR C 283 27.031 100.134 25.234 0.00 0.00 ATOM 54 CA TRP C 284 27.489 96.279 25.050 0.00 0.00 ATOM 55 CA THR C 285 25.359 93.678 26.983 0.00 0.00 ATOM 56 CA PRO C 286 27.583 91.299 29.115 0.00 0.00 ATOM 57 CA SER C 287 28.065 87.572 28.151 0.00 0.00 ATOM 58 CA SER C 288 26.329 84.917 30.386 0.00 0.00 ATOM 59 CA GLY C 289 29.067 84.492 33.111 0.00 0.00 ATOM 60 CA LYS C 290 28.864 88.256 34.097 0.00 0.00 ATOM 61 CA SER C 291 31.493 89.436 31.520 0.00 0.00 ATOM 62 CA ALA C 292 31.660 92.796 29.586 0.00 0.00 ATOM 63 CA VAL C 293 35.131 93.771 28.128 0.00 0.00 ATOM 64 CA GLN C 294 35.669 96.304 25.214 0.00 0.00 ATOM 65 CA GLY C 295 38.439 98.151 23.179 0.00 0.00 ATOM 66 CA PRO C 296 37.265 101.025 20.845 0.00 0.00 ATOM 67 CA PRO C 297 39.775 102.874 18.491 0.00 0.00 ATOM 68 CA GLU C 298 38.726 105.609 15.938 0.00 0.00 ATOM 69 CA ARG C 299 39.996 104.836 12.386 0.00 0.00 ATOM 70 CA ASP C 300 39.510 107.283 9.419 0.00 0.00 ATOM 71 CA LEU C 301 38.429 104.985 6.460 0.00 0.00 ATOM 72 CA CYS C 302 37.819 106.463 2.900 0.00 0.00 ATOM 73 CA GLY C 303 37.863 109.996 4.418 0.00 0.00 ATOM 74 CA CYS C 304 35.690 109.601 7.621 0.00 0.00 ATOM 75 CA TYR C 305 35.839 108.101 11.217 0.00 0.00 ATOM 76 CA SER C 306 34.926 104.451 12.161 0.00 0.00 ATOM 77 CA VAL C 307 34.594 103.430 15.893 0.00 0.00 ATOM 78 CA SER C 308 35.247 99.687 15.788 0.00 0.00 ATOM 79 CA SER C 309 34.807 98.113 19.228 0.00 0.00 ATOM 80 CA VAL C 310 35.162 94.364 20.049 0.00 0.00 ATOM 81 CA LEU C 311 33.587 92.215 22.850 0.00 0.00 ATOM 82 CA PRO C 312 35.519 88.916 23.586 0.00 0.00 ATOM 83 CA GLY C 313 33.163 85.950 24.328 0.00 0.00 ATOM 84 CA CYS C 314 33.156 82.317 25.555 0.00 0.00 ATOM 85 CA ALA C 315 31.723 79.222 23.707 0.00 0.00 ATOM 86 CA GLU C 316 28.863 78.508 26.268 0.00 0.00 ATOM 87 CA PRO C 317 26.814 81.812 25.776 0.00 0.00 ATOM 88 CA TRP C 318 27.027 81.373 21.921 0.00 0.00 ATOM 89 CA ASN C 319 26.178 77.562 22.015 0.00 0.00 ATOM 90 CA HIS C 320 23.338 77.786 24.692 0.00 0.00 ATOM 91 CA GLY C 321 21.533 80.954 23.342 0.00 0.00 ATOM 92 CA LYS C 322 22.648 84.518 24.368 0.00 0.00 ATOM 93 CA THR C 323 21.582 87.865 22.710 0.00 0.00 ATOM 94 CA PHE C 324 24.545 90.282 22.170 0.00 0.00 ATOM 95 CA THR C 325 23.455 93.921 21.875 0.00 0.00 ATOM 96 CA CYS C 326 25.796 96.692 20.640 0.00 0.00 ATOM 97 CA THR C 327 24.014 99.996 21.363 0.00 0.00 ATOM 98 CA ALA C 328 25.888 103.034 20.027 0.00 0.00 ATOM 99 CA ALA C 329 25.069 106.710 20.963 0.00 0.00 ATOM 100 CA TYR C 330 26.148 109.903 19.007 0.00 0.00 ATOM 101 CA PRO C 331 24.513 113.469 19.075 0.00 0.00 ATOM 102 CA GLU C 332 23.957 113.743 15.228 0.00 0.00 ATOM 103 CA SER C 333 22.273 110.230 15.350 0.00 0.00 ATOM 104 CA LYS C 334 18.954 111.349 17.048 0.00 0.00 ATOM 105 CA THR C 335 17.962 107.685 17.796 0.00 0.00 ATOM 106 CA PRO C 336 20.952 105.769 19.408 0.00 0.00 ATOM 107 CA LEU C 337 21.446 102.615 17.224 0.00 0.00 ATOM 108 CA THR C 338 20.913 99.210 18.825 0.00 0.00 ATOM 109 CA ALA C 339 22.026 96.028 16.919 0.00 0.00 ATOM 110 CA THR C 340 21.464 92.595 18.588 0.00 0.00 ATOM 111 CA LEU C 341 22.950 89.220 17.568 0.00 0.00 ATOM 112 CA SER C 342 22.599 85.514 18.724 0.00 0.00 ATOM 113 CA LYS C 343 22.306 81.818 17.533 0.00 0.00 ATOM 114 CA SER C 344 19.702 80.671 14.883 0.00 0.00 ATOM 115 CA GLY C 345 16.235 78.933 14.952 0.00 0.00 TER