Knowledge (XXG)

Molecular replacement

Source đź“ť

1232: 1625: 77: 1637: 22: 524:
In the translation function, the now correctly oriented known model can be correctly positioned by translating it to the correct co-ordinates within the asymmetric unit. This is accomplished by moving the model, calculating a new Patterson map, and comparing it to the unknown-derived Patterson map.
472:
for the intensities, which is an interatomic vector map created by squaring the structure factor amplitudes and setting all phases to zero. This vector map contains a peak for each atom related to every other atom, with a large peak at 0,0,0, where vectors relating atoms to themselves "pile up".
473:
Such a map is far too noisy to derive any high resolution structural information—however if we generate Patterson maps for the data derived from our unknown structure, and from the structure of a previously solved homologue, in the correct orientation and position within the
384: 560:
Following this, we should have correctly oriented and translated phasing models, from which we can derive phases which are (hopefully) accurate enough to derive electron density maps. These can be used to build and refine an atomic model of our unknown structure.
477:, the two Patterson maps should be closely correlated. This principle lies at the heart of MR, and can allow us to infer information about the orientation and location of an unknown molecule with its unit cell. 1502: 1497: 201: 1553: 508:-based algorithms. The highest correlation (and therefore scores) are obtained when the two structures (known and unknown) are in similar orientation(s)—these can then be output in 184:. MR relies upon the existence of a previously solved protein structure which is similar to our unknown structure from which the diffraction data is derived. This could come from a 426: 40: 496:
In the rotation function, our unknown Patterson map is compared to Patterson maps derived from our known homologue structure in different orientations. Historically
460:) to real-space electron density, into which the atomic model is built. MR tries to find the model which fits best experimental intensities among known structures. 446: 501: 525:
This brute-force search is computationally expensive and fast translation functions are now more commonly used. Positions with high correlations are output in
1371: 704: 640:
Jin, Shikai; Miller, Mitchell D.; Chen, Mingchen; Schafer, Nicholas P.; Lin, Xingcheng; Chen, Xun; Phillips, George N.; Wolynes, Peter G. (1 November 2020).
548:, many protocols including MR-Rosetta, QUARK, AWSEM-Suite and I-TASSER-MR can generate a lot of native-like decoy structures that are useful to solve the 1558: 1283: 1449: 741: 1548: 1540: 94: 1601: 1579: 1594: 1444: 1110: 975: 824: 1584: 1482: 1178: 831: 1606: 1464: 1434: 1363: 195:
The first goal of the crystallographer is to obtain an electron density map, density being related with diffracted wave as follows:
160: 141: 58: 379:{\displaystyle \rho (x,y,z)={\frac {1}{V}}\sum _{h}\sum _{k}\sum _{\ell }|F_{hk\ell }|\exp(2\pi i(hx+ky+\ell z)+i\Phi (hk\ell )).} 113: 1316: 1589: 1512: 1386: 985: 1346: 1663: 1424: 120: 98: 591:
Ramelot, TA; Raman, S; Kuzin, AP; Xiao, R; Ma, LC; Acton, TB; Hunt, JF; Montelione, GT; Baker, D; Kennedy, MA (April 2009).
1439: 1429: 734: 1211: 1563: 836: 814: 545: 1241: 1115: 127: 869: 764: 1231: 1641: 1472: 769: 497: 109: 87: 1487: 1416: 874: 864: 1000: 1629: 1353: 1249: 1122: 1085: 879: 859: 727: 1037: 1477: 1321: 1266: 1015: 980: 1173: 990: 1095: 1530: 1288: 1047: 781: 526: 513: 453: 181: 1254: 1127: 963: 854: 392: 1271: 1259: 1134: 1100: 1080: 134: 480:
Due to historic limitations in computing power, an MR search is typically divided into two steps:
1520: 1331: 1276: 819: 505: 469: 185: 1454: 1293: 1221: 1201: 921: 791: 673: 622: 593:"Improving NMR protein structure quality by Rosetta refinement: a molecular replacement study" 449: 1492: 1298: 1216: 1206: 1005: 938: 909: 902: 663: 653: 612: 604: 457: 431: 1381: 1376: 1341: 1161: 1060: 995: 958: 953: 804: 750: 1191: 1156: 1144: 1139: 1105: 1075: 1065: 1024: 968: 892: 846: 668: 641: 617: 592: 1657: 1336: 1149: 948: 549: 177: 1042: 1032: 926: 809: 642:"Molecular-replacement phasing using predicted protein structures from AWSEM-Suite" 509: 448:) is lost. Then, in the absence of phases (Φ), we are unable to complete the shown 1525: 1196: 1070: 897: 485: 189: 76: 1090: 776: 658: 578: 799: 474: 677: 626: 1396: 1166: 914: 709: 700: 481: 1406: 608: 504:
were used to score the rotation function, however, modern programs use
694: 1401: 719: 697:– One of the most commonly used molecular replacement programmes. 723: 70: 15: 577:
Ch 10 in "Principles of Protein X-ray Crystallography", by
1503:
Zeitschrift für Kristallographie – New Crystal Structures
1498:
Zeitschrift für Kristallographie – Crystalline Materials
428:
is being measured, and all the information about phase (
36: 1391: 713: 434: 395: 204: 716:– A helpful public domain introduction to the topic. 1572: 1539: 1511: 1463: 1415: 1362: 1309: 1240: 1023: 1014: 937: 845: 790: 757: 464:
Principles of Patterson-based molecular replacement
101:. Unsourced material may be challenged and removed. 31:
may be too technical for most readers to understand
440: 420: 378: 735: 537:predicted structures in molecular replacement 8: 1569: 1020: 842: 787: 742: 728: 720: 667: 657: 616: 433: 412: 394: 293: 281: 272: 266: 256: 246: 232: 203: 161:Learn how and when to remove this message 59:Learn how and when to remove this message 43:, without removing the technical details. 703:– Molecular replacement package within 570: 188:protein, or from the lower-resolution 41:make it understandable to non-experts 7: 1636: 976:Phase transformation crystallography 452:relating the experimental data from 99:adding citations to reliable sources 1483:Journal of Chemical Crystallography 389:With usual detectors the intensity 435: 352: 14: 1635: 1624: 1623: 1230: 75: 20: 192:structure of the same protein. 86:needs additional citations for 1425:Bilbao Crystallographic Server 421:{\displaystyle I=F\cdot F^{*}} 370: 367: 355: 343: 316: 304: 294: 273: 226: 208: 1: 546:protein structure prediction 1473:Crystal Growth & Design 765:Timeline of crystallography 176:is a method of solving the 1680: 1284:Nuclear magnetic resonance 552:by molecular replacement. 174:Molecular replacement (MR) 1619: 1488:Journal of Crystal Growth 1228: 659:10.1107/S2052252520013494 581:(2nd Edn.) Springer, 1999 1354:Single particle analysis 1212:Hermann–Mauguin notation 541:With the improvement of 502:correlation coefficients 1478:Crystallography Reviews 1322:Isomorphous replacement 1116:Lomer–Cottrell junction 110:"Molecular replacement" 991:Spinodal decomposition 442: 422: 380: 1664:X-ray crystallography 1531:Gregori Aminoff Prize 1327:Molecular replacement 527:Cartesian coordinates 454:X-ray crystallography 443: 441:{\displaystyle \Phi } 423: 381: 182:X-ray crystallography 837:Structure prediction 520:Translation function 432: 393: 202: 95:improve this article 1101:Cottrell atmosphere 1081:Partial dislocation 825:Restriction theorem 1521:Carl Hermann Medal 1332:Molecular dynamics 1179:Defects in diamond 1174:Stone–Wales defect 820:Reciprocal lattice 782:Biocrystallography 609:10.1002/prot.22229 506:maximum likelihood 438: 418: 376: 271: 261: 251: 1651: 1650: 1615: 1614: 1222:Thermal ellipsoid 1187: 1186: 1096:Frank–Read source 1056: 1055: 922:Aperiodic crystal 888: 887: 770:Crystallographers 492:Rotation function 450:Fourier transform 262: 252: 242: 240: 171: 170: 163: 145: 69: 68: 61: 1671: 1639: 1638: 1627: 1626: 1570: 1493:Kristallografija 1347:Gerchberg–Saxton 1242:Characterisation 1234: 1217:Structure factor 1021: 1006:Ostwald ripening 843: 788: 744: 737: 730: 721: 682: 681: 671: 661: 652:(6): 1168–1178. 637: 631: 630: 620: 588: 582: 575: 468:We can derive a 458:reciprocal space 447: 445: 444: 439: 427: 425: 424: 419: 417: 416: 385: 383: 382: 377: 297: 292: 291: 276: 270: 260: 250: 241: 233: 166: 159: 155: 152: 146: 144: 103: 79: 71: 64: 57: 53: 50: 44: 24: 23: 16: 1679: 1678: 1674: 1673: 1672: 1670: 1669: 1668: 1654: 1653: 1652: 1647: 1611: 1568: 1535: 1507: 1459: 1411: 1382:CrystalExplorer 1358: 1342:Phase retrieval 1305: 1236: 1235: 1226: 1183: 1162:Schottky defect 1061:Perfect crystal 1052: 1048:Abnormal growth 1010: 996:Supersaturation 959:Miscibility gap 940: 933: 884: 841: 805:Bravais lattice 786: 753: 751:Crystallography 748: 691: 686: 685: 639: 638: 634: 590: 589: 585: 576: 572: 567: 558: 539: 522: 514:spherical polar 494: 466: 430: 429: 408: 391: 390: 277: 200: 199: 167: 156: 150: 147: 104: 102: 92: 80: 65: 54: 48: 45: 37:help improve it 34: 25: 21: 12: 11: 5: 1677: 1675: 1667: 1666: 1656: 1655: 1649: 1648: 1646: 1645: 1633: 1620: 1617: 1616: 1613: 1612: 1610: 1609: 1604: 1599: 1598: 1597: 1592: 1587: 1576: 1574: 1567: 1566: 1561: 1556: 1551: 1545: 1543: 1537: 1536: 1534: 1533: 1528: 1523: 1517: 1515: 1509: 1508: 1506: 1505: 1500: 1495: 1490: 1485: 1480: 1475: 1469: 1467: 1461: 1460: 1458: 1457: 1452: 1447: 1442: 1437: 1432: 1427: 1421: 1419: 1413: 1412: 1410: 1409: 1404: 1399: 1394: 1389: 1384: 1379: 1374: 1368: 1366: 1360: 1359: 1357: 1356: 1351: 1350: 1349: 1339: 1334: 1329: 1324: 1319: 1317:Direct methods 1313: 1311: 1307: 1306: 1304: 1303: 1302: 1301: 1296: 1286: 1281: 1280: 1279: 1274: 1264: 1263: 1262: 1257: 1246: 1244: 1238: 1237: 1229: 1227: 1225: 1224: 1219: 1214: 1209: 1204: 1202:Ewald's sphere 1199: 1194: 1188: 1185: 1184: 1182: 1181: 1176: 1171: 1170: 1169: 1164: 1154: 1153: 1152: 1147: 1145:Frenkel defect 1142: 1140:Bjerrum defect 1132: 1131: 1130: 1120: 1119: 1118: 1113: 1108: 1106:Peierls stress 1103: 1098: 1093: 1088: 1083: 1078: 1076:Burgers vector 1068: 1066:Stacking fault 1063: 1057: 1054: 1053: 1051: 1050: 1045: 1040: 1035: 1029: 1027: 1025:Grain boundary 1018: 1012: 1011: 1009: 1008: 1003: 998: 993: 988: 983: 978: 973: 972: 971: 969:Liquid crystal 966: 961: 956: 945: 943: 935: 934: 932: 931: 930: 929: 919: 918: 917: 907: 906: 905: 900: 889: 886: 885: 883: 882: 877: 872: 867: 862: 857: 851: 849: 840: 839: 834: 832:Periodic table 829: 828: 827: 822: 817: 812: 807: 796: 794: 785: 784: 779: 774: 773: 772: 761: 759: 755: 754: 749: 747: 746: 739: 732: 724: 718: 717: 710:Phaser article 707: 698: 690: 689:External links 687: 684: 683: 632: 583: 569: 568: 566: 563: 557: 554: 538: 531: 521: 518: 493: 490: 465: 462: 437: 415: 411: 407: 404: 401: 398: 387: 386: 375: 372: 369: 366: 363: 360: 357: 354: 351: 348: 345: 342: 339: 336: 333: 330: 327: 324: 321: 318: 315: 312: 309: 306: 303: 300: 296: 290: 287: 284: 280: 275: 269: 265: 259: 255: 249: 245: 239: 236: 231: 228: 225: 222: 219: 216: 213: 210: 207: 169: 168: 83: 81: 74: 67: 66: 28: 26: 19: 13: 10: 9: 6: 4: 3: 2: 1676: 1665: 1662: 1661: 1659: 1644: 1643: 1634: 1632: 1631: 1622: 1621: 1618: 1608: 1605: 1603: 1600: 1596: 1593: 1591: 1588: 1586: 1583: 1582: 1581: 1578: 1577: 1575: 1571: 1565: 1562: 1560: 1557: 1555: 1552: 1550: 1547: 1546: 1544: 1542: 1538: 1532: 1529: 1527: 1524: 1522: 1519: 1518: 1516: 1514: 1510: 1504: 1501: 1499: 1496: 1494: 1491: 1489: 1486: 1484: 1481: 1479: 1476: 1474: 1471: 1470: 1468: 1466: 1462: 1456: 1453: 1451: 1448: 1446: 1443: 1441: 1438: 1436: 1433: 1431: 1428: 1426: 1423: 1422: 1420: 1418: 1414: 1408: 1405: 1403: 1400: 1398: 1395: 1393: 1390: 1388: 1385: 1383: 1380: 1378: 1375: 1373: 1370: 1369: 1367: 1365: 1361: 1355: 1352: 1348: 1345: 1344: 1343: 1340: 1338: 1337:Patterson map 1335: 1333: 1330: 1328: 1325: 1323: 1320: 1318: 1315: 1314: 1312: 1308: 1300: 1297: 1295: 1292: 1291: 1290: 1287: 1285: 1282: 1278: 1275: 1273: 1270: 1269: 1268: 1265: 1261: 1258: 1256: 1253: 1252: 1251: 1248: 1247: 1245: 1243: 1239: 1233: 1223: 1220: 1218: 1215: 1213: 1210: 1208: 1207:Friedel's law 1205: 1203: 1200: 1198: 1195: 1193: 1190: 1189: 1180: 1177: 1175: 1172: 1168: 1165: 1163: 1160: 1159: 1158: 1155: 1151: 1150:Wigner effect 1148: 1146: 1143: 1141: 1138: 1137: 1136: 1135:Interstitials 1133: 1129: 1126: 1125: 1124: 1121: 1117: 1114: 1112: 1109: 1107: 1104: 1102: 1099: 1097: 1094: 1092: 1089: 1087: 1084: 1082: 1079: 1077: 1074: 1073: 1072: 1069: 1067: 1064: 1062: 1059: 1058: 1049: 1046: 1044: 1041: 1039: 1036: 1034: 1031: 1030: 1028: 1026: 1022: 1019: 1017: 1013: 1007: 1004: 1002: 999: 997: 994: 992: 989: 987: 984: 982: 981:Precipitation 979: 977: 974: 970: 967: 965: 962: 960: 957: 955: 952: 951: 950: 949:Phase diagram 947: 946: 944: 942: 936: 928: 925: 924: 923: 920: 916: 913: 912: 911: 908: 904: 901: 899: 896: 895: 894: 891: 890: 881: 878: 876: 873: 871: 868: 866: 863: 861: 858: 856: 853: 852: 850: 848: 844: 838: 835: 833: 830: 826: 823: 821: 818: 816: 813: 811: 808: 806: 803: 802: 801: 798: 797: 795: 793: 789: 783: 780: 778: 775: 771: 768: 767: 766: 763: 762: 760: 756: 752: 745: 740: 738: 733: 731: 726: 725: 722: 715: 711: 708: 706: 702: 699: 696: 693: 692: 688: 679: 675: 670: 665: 660: 655: 651: 647: 643: 636: 633: 628: 624: 619: 614: 610: 606: 603:(1): 147–67. 602: 598: 594: 587: 584: 580: 574: 571: 564: 562: 556:The next step 555: 553: 551: 550:phase problem 547: 544: 536: 532: 530: 528: 519: 517: 515: 511: 507: 503: 499: 491: 489: 487: 483: 478: 476: 471: 470:Patterson map 463: 461: 459: 455: 451: 413: 409: 405: 402: 399: 396: 373: 364: 361: 358: 349: 346: 340: 337: 334: 331: 328: 325: 322: 319: 313: 310: 307: 301: 298: 288: 285: 282: 278: 267: 263: 257: 253: 247: 243: 237: 234: 229: 223: 220: 217: 214: 211: 205: 198: 197: 196: 193: 191: 187: 183: 179: 178:phase problem 175: 165: 162: 154: 143: 140: 136: 133: 129: 126: 122: 119: 115: 112: â€“  111: 107: 106:Find sources: 100: 96: 90: 89: 84:This article 82: 78: 73: 72: 63: 60: 52: 42: 38: 32: 29:This article 27: 18: 17: 1640: 1628: 1573:Associations 1541:Organisation 1326: 1033:Disclination 964:Polymorphism 927:Quasicrystal 870:Orthorhombic 810:Miller index 758:Key concepts 649: 645: 635: 600: 596: 586: 573: 559: 542: 540: 534: 523: 510:Euler angles 495: 479: 467: 388: 194: 173: 172: 157: 148: 138: 131: 124: 117: 105: 93:Please help 88:verification 85: 55: 46: 30: 1526:Ewald Prize 1294:Diffraction 1272:Diffraction 1255:Diffraction 1197:Bragg plane 1192:Bragg's law 1071:Dislocation 986:Segregation 898:Crystallite 815:Point group 486:translation 190:protein NMR 1310:Algorithms 1299:Scattering 1277:Scattering 1260:Scattering 1128:Slip bands 1091:Cross slip 941:transition 875:Tetragonal 865:Monoclinic 777:Metallurgy 579:Jan Drenth 565:References 186:homologous 151:April 2019 121:newspapers 1417:Databases 880:Triclinic 860:Hexagonal 800:Unit cell 792:Structure 498:r-factors 475:unit cell 436:Φ 414:∗ 406:⋅ 365:ℓ 353:Φ 338:ℓ 311:π 302:⁡ 289:ℓ 268:ℓ 264:∑ 254:∑ 244:∑ 206:ρ 1658:Category 1630:Category 1465:Journals 1397:OctaDist 1392:JANA2020 1364:Software 1250:Electron 1167:F-center 954:Eutectic 915:Fiveling 910:Twinning 903:Equiaxed 678:33209327 627:18816799 597:Proteins 516:angles. 482:rotation 49:May 2012 1642:Commons 1590:Germany 1267:Neutron 1157:Vacancy 1016:Defects 1001:GP-zone 847:Systems 669:7642774 618:3612016 543:de novo 535:de novo 500:and/or 135:scholar 35:Please 1585:France 1580:Europe 1513:Awards 1043:Growth 893:Growth 701:Molrep 695:Phaser 676:  666:  625:  615:  533:Using 137:  130:  123:  116:  108:  1607:Japan 1554:IOBCr 1407:SHELX 1402:Olex2 1289:X-ray 939:Phase 855:Cubic 646:IUCrJ 142:JSTOR 128:books 1549:IUCr 1450:ICDD 1445:ICSD 1430:CCDC 1377:Coot 1372:CCP4 1123:Slip 1086:Kink 714:PDBe 705:CCP4 674:PMID 623:PMID 484:and 456:(in 114:news 1564:DMG 1559:RAS 1455:PDB 1440:COD 1435:CIF 1387:DSR 1111:GND 1038:CSL 712:at 664:PMC 654:doi 613:PMC 605:doi 512:or 299:exp 180:in 97:by 39:to 1660:: 1602:US 1595:UK 672:. 662:. 648:. 644:. 621:. 611:. 601:75 599:. 595:. 529:. 488:. 743:e 736:t 729:v 680:. 656:: 650:7 629:. 607:: 410:F 403:F 400:= 397:I 374:. 371:) 368:) 362:k 359:h 356:( 350:i 347:+ 344:) 341:z 335:+ 332:y 329:k 326:+ 323:x 320:h 317:( 314:i 308:2 305:( 295:| 286:k 283:h 279:F 274:| 258:k 248:h 238:V 235:1 230:= 227:) 224:z 221:, 218:y 215:, 212:x 209:( 164:) 158:( 153:) 149:( 139:· 132:· 125:· 118:· 91:. 62:) 56:( 51:) 47:( 33:.

Index

help improve it
make it understandable to non-experts
Learn how and when to remove this message

verification
improve this article
adding citations to reliable sources
"Molecular replacement"
news
newspapers
books
scholar
JSTOR
Learn how and when to remove this message
phase problem
X-ray crystallography
homologous
protein NMR
Fourier transform
X-ray crystallography
reciprocal space
Patterson map
unit cell
rotation
translation
r-factors
correlation coefficients
maximum likelihood
Euler angles
spherical polar

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑