9GDA: RNAP-TopoI complex on duplex scaffold

RNAP-TopoI complex on duplex scaffold. Determined by electron microscopy at 2.7 Å resolution. Released 5 Nov 2025.

Method
Electron microscopy
Resolution
2.7 Å
Organisms
Escherichia coli, synthetic construct
Chains
9
Atoms
33,857
Mol. weight
520.03 kDa
Ligands
MG, ZN
Released
5 Nov 2025

Explore 9GDA in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9GDA contains 207 α-helices and 256 β-strands across 6 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 8 helices, 16 β-strands

ElementResiduesLengthSheet
α-helix8-114
β-strand12-1871
β-strand23-3191
α-helix35-5016
β-strand52-61102
β-strand7413
α-helix78-869
β-strand90-9234
β-strand97-10592
β-strand108-11143
α-helix112-1143
β-strand115-11622
α-helix117-1182
β-strand121-12334
β-strand129-13353
β-strand139-150122
β-strand152-15325
α-helix155-1584
α-helix159-1613
β-strand170-17232
β-strand175-17625
β-strand180-189101
β-strand199-20791
α-helix213-23321
Chain B: 7 helices, 15 β-strands
ElementResiduesLengthSheet
β-strand13-1866
β-strand23-32106
α-helix35-4915
β-strand52-61107
β-strand7418
α-helix78-869
β-strand90-9239
β-strand97-10597
β-strand108-11148
α-helix112-1143
α-helix116-1172
β-strand121-12339
β-strand129-13358
β-strand139-150127
β-strand152-153210
α-helix155-1584
α-helix161-1633
β-strand170-17237
β-strand175-176210
β-strand180-190116
β-strand197-207116
α-helix213-22816
Chain C: 70 helices, 94 β-strands
ElementResiduesLengthSheet
α-helix7-93
α-helix11-122
β-strand13-14211
α-helix19-202
α-helix23-264
α-helix29-3911
α-helix48-569
β-strand59-60212
β-strand66-751012
α-helix76-783
α-helix82-887
β-strand93-1051312
β-strand114-1281512
α-helix129-1302
β-strand136-137213
β-strand142-145413
β-strand147-151514
α-helix1521
β-strand154-159615
α-helix166-1683
β-strand172-177615
β-strand180116
β-strand184-188515
β-strand194-198515
β-strand204-205215
α-helix206-2127
α-helix217-2248
β-strand227-233717
β-strand236-240517
α-helix243-2464
β-strand250118
β-strand256-257219
β-strand260-261219
β-strand268118
α-helix271-28010
β-strand284-286317
α-helix289-2924
α-helix2951
β-strand296-297217
β-strand301-302220
β-strand309-311320
α-helix3151
β-strand316117
α-helix3171
α-helix319-32810
β-strand332-336517
β-strand339121
β-strand343121
α-helix346-3538
α-helix359-37012
α-helix378-38912
β-strand396116
α-helix399-40810
α-helix422-43716
β-strand451-454414
α-helix456-48025
α-helix489-4913
α-helix496-50813
β-strand512-514313
α-helix520-5278
β-strand529-531314
α-helix545-5484
α-helix552-5543
β-strand558122
α-helix566-5683
β-strand572-574314
β-strand575122
β-strand580-581223
β-strand587-595923
β-strand598-6071023
α-helix608-6136
β-strand616-617223
β-strand623124
β-strand629124
β-strand633-636423
β-strand643-646423
β-strand652-654323
α-helix663-6664
α-helix671-6733
β-strand674125
α-helix676-68611
α-helix689-6913
β-strand700-701211
α-helix705-7117
β-strand716-717226
β-strand722-727627
β-strand731-736627
α-helix738-7403
α-helix7421
β-strand748-752527
α-helix753-7542
β-strand757-758228
β-strand763129
β-strand764-765228
β-strand768-769226
β-strand776-777227
β-strand782-785426
β-strand789-790230
β-strand793-794230
β-strand798-804731
β-strand816-819431
α-helix820-8245
β-strand830-8411229
β-strand842-843232
β-strand846-847232
β-strand849-850233
α-helix859-8624
β-strand865134
β-strand870135
β-strand871134
α-helix8721
β-strand876-877229
β-strand882-884335
β-strand886-889433
α-helix897-90610
β-strand913-915333
β-strand918-919235
α-helix920-9212
β-strand926-9351029
β-strand936136
α-helix940-9412
α-helix943-98139
α-helix986-9916
α-helix994-9996
α-helix1006-103732
β-strand1040136
α-helix1042-10432
β-strand1046-10581329
β-strand1065-1067337
β-strand1073-1075337
β-strand1076-1080531
α-helix1082-10843
β-strand1087138
α-helix10921
β-strand1093138
α-helix10941
β-strand1096-1098331
α-helix1102-11065
β-strand1108125
α-helix1110-113324
α-helix1138-115013
α-helix1161-11633
α-helix1166-117510
β-strand1182-1183211
α-helix1192-120110
β-strand1209-1210231
β-strand1213138
α-helix12191
β-strand1220138
α-helix12211
β-strand1225-1232831
β-strand1233-1234237
α-helix1239-12413
β-strand1244-1246339
β-strand1251140
β-strand1258140
α-helix1266-12683
β-strand1269-1270241
α-helix1272-12809
α-helix1284-12885
α-helix1289-12968
α-helix1298-131013
α-helix1321-133111
β-strand1335-1340642
Chain D: 79 helices, 82 β-strands
ElementResiduesLengthSheet
β-strand19-24642
α-helix25-262
α-helix27-337
β-strand34-37443
β-strand44144
β-strand51144
α-helix59-624
α-helix78-803
α-helix831
β-strand84145
α-helix851
β-strand91145
α-helix95-995
β-strand102-1121143
α-helix115-1184
α-helix123-1286
α-helix132-1398
β-strand144-149646
β-strand159-160246
α-helix162-17211
β-strand176-179446
α-helix181-19010
α-helix194-20714
α-helix211-23020
α-helix234-2374
β-strand238-244743
α-helix247-2493
β-strand252-254347
β-strand260-262347
α-helix264-28421
α-helix289-30719
α-helix315-3162
β-strand317148
β-strand323148
α-helix324-3252
α-helix327-3315
α-helix337-3426
β-strand345-346241
β-strand350-354539
β-strand355-357349
β-strand365-369549
α-helix370-3767
α-helix378-38710
α-helix394-40310
α-helix406-41510
β-strand421-424439
α-helix431-4333
β-strand434-437439
β-strand438-442549
β-strand447-449349
α-helix451-4533
α-helix454-4574
β-strand465-469539
α-helix474-4796
α-helix480-4845
β-strand485139
α-helix486-4883
β-strand491150
β-strand498150
α-helix505-5139
β-strand526-527251
α-helix530-53910
β-strand547-5571151
α-helix5621
β-strand563-5731151
α-helix574-5807
α-helix5841
α-helix589-5913
α-helix598-61215
α-helix614-63522
α-helix641-6433
α-helix645-6473
α-helix650-66920
α-helix675-70228
β-strand703-707552
β-strand713-717552
α-helix721-7288
α-helix734-7418
β-strand745153
β-strand748154
α-helix7531
β-strand754154
α-helix7551
β-strand759153
α-helix766-7683
α-helix769-80436
β-strand809-811355
β-strand820-822356
β-strand825-827357
β-strand830-833457
α-helix835-8395
β-strand843158
β-strand844156
α-helix8471
β-strand848-849259
α-helix8501
β-strand856-858359
β-strand863158
α-helix866-8749
β-strand880-882356
α-helix885-8873
β-strand894-895255
α-helix896-8994
β-strand901160
β-strand908160
α-helix909-9102
α-helix915-92410
α-helix925-9295
β-strand951161
β-strand956-961662
β-strand965-967363
β-strand973-975363
β-strand980-985662
β-strand991-997762
α-helix9981
β-strand1002-1003263
β-strand1010-1011262
β-strand1016161
β-strand1028164
β-strand1033-1038665
β-strand1042166
β-strand1046-1050566
β-strand1057-1061566
α-helix1062-10632
α-helix1069-10713
β-strand1077-1081565
α-helix10861
β-strand1087165
α-helix10881
β-strand1089167
α-helix10901
β-strand1096167
β-strand1098-1100365
β-strand1106-1107266
β-strand1113-1115365
β-strand1120164
α-helix1138-11469
α-helix1148-11503
α-helix1153-11542
β-strand1155-1156268
β-strand1161-1165569
β-strand1172-1178769
β-strand1186-1191669
β-strand1196168
β-strand1203-1204269
β-strand1209-1211368
α-helix1214-12163
α-helix1217-12237
α-helix1226-124419
α-helix1250-126011
β-strand1263-1268670
β-strand1279-1281370
α-helix1282-129413
α-helix1297-13004
β-strand1301-1305570
α-helix1309-13146
α-helix1319-13257
α-helix1328-133811
β-strand1341-1342242
α-helix1347-13537
α-helix1361-137515
Chain E: 5 helices, 0 β-strands
ElementResiduesLengthSheet
α-helix7-137
α-helix16-3116
α-helix35-373
α-helix46-5510
α-helix61-9030
Chain F: 38 helices, 49 β-strands
ElementResiduesLengthSheet
β-strand4-8571
α-helix11-2111
β-strand25-29571
β-strand36172
α-helix62-7110
β-strand74173
β-strand80173
β-strand84172
α-helix90-10213
β-strand106-108371
α-helix114-12714
β-strand134-136371
α-helix144-1529
α-helix1541
β-strand155171
α-helix156-1572
α-helix159-18628
α-helix195-21319
β-strand218-2271074
β-strand233-241974
β-strand244-245274
α-helix251-26313
β-strand267-2781274
α-helix279-2835
β-strand284175
α-helix2851
α-helix286-2927
α-helix293-2975
α-helix301-31414
β-strand317176
α-helix329-34214
α-helix345-3473
β-strand368175
β-strand370176
α-helix377-3793
α-helix385-40016
α-helix404-4052
β-strand406-4171274
β-strand420-4311274
α-helix453-4542
β-strand457-458274
β-strand460-461274
β-strand465-470674
α-helix471-4788
α-helix479-48911
α-helix497-50610
β-strand510-513477
β-strand516-519477
α-helix521-53313
α-helix535-5384
α-helix540-55415
α-helix560-57920
β-strand593-595378
β-strand606-611678
β-strand614-619678
α-helix620-6234
α-helix626-6283
β-strand633-635378
β-strand637-638279
α-helix639-6413
α-helix645-6473
α-helix650-6589
β-strand661180
β-strand668180
β-strand669-673579
β-strand678-683679
β-strand692-696579
β-strand709-710281
β-strand717-723781
β-strand726-731681
β-strand739-741381
α-helix752-7554
β-strand756-762782
β-strand769-774682
β-strand779-783582
α-helix786-7894
β-strand792-793282
α-helix794-7952
β-strand796183
α-helix797-8026
α-helix812-8165
β-strand820184
β-strand826184
β-strand827-832683
β-strand837-844883
β-strand847-855983
β-strand860-864583

Molecules and chains

MoleculeChainsTypeLengthOrganismUniProt
DNA-directed RNA polymerase subunit alphaA, Bprotein329Escherichia coliP0A7Z4 (AlphaFold model)
DNA-directed RNA polymerase subunit betaCprotein1342Escherichia coliP0A8V2 (AlphaFold model)
DNA-directed RNA polymerase subunit beta'Dprotein1415Escherichia coliP0A8T7 (AlphaFold model)
DNA-directed RNA polymerase subunit omegaEprotein91Escherichia coliP0A800 (AlphaFold model)
DNA topoisomerase 1Fprotein896Escherichia coliP06612
non-template DNA strandNDNA39synthetic construct
RNARRNA14synthetic construct
template DNA strandTDNA39synthetic construct
Sequence of entity 1 (A, B), FASTA
>9GDA_1 DNA-directed RNA polymerase subunit alpha (chains A, B)
MQGSVTEFLKPRLVDIEQVSSTHAKVTLEPLERGFGHTLGNALRRILLSSMPGCAVTEVE
IDGVLHEYSTKEGVQEDILEILLNLKGLAVRVQGKDEVILTLNKSGIGPVTAADITHDGD
VEIVKPQHVICHLTDENASISMRIKVQRGRGYVPASTRIHSEEDERPIGRLLVDACYSPV
ERIAYNVEAARVEQRTDLDKLVIEMETNGTIDPEEAIRRAATILAEQLEAFVDLRDVRQP
EVKEEKPEFDPILLRPVDDLELTVRSANCLKAEAIHYIGDLVQRTEVELLKTPNLGKKSL
TEIKDVLASRGLSLGMRLENWPPASIADE
Sequence of entity 2 (C), FASTA
>9GDA_2 DNA-directed RNA polymerase subunit beta (chains C)
MVYSYTEKKRIRKDFGKRPQVLDVPYLLSIQLDSFQKFIEQDPEGQYGLEAAFRSVFPIQ
SYSGNSELQYVSYRLGEPVFDVQECQIRGVTYSAPLRVKLRLVIYEREAPEGTVKDIKEQ
EVYMGEIPLMTDNGTFVINGTERVIVSQLHRSPGVFFDSDKGKTHSSGKVLYNARIIPYR
GSWLDFEFDPKDNLFVRIDRRRKLPATIILRALNYTTEQILDLFFEKVIFEIRDNKLQME
LVPERLRGETASFDIEANGKVYVEKGRRITARHIRQLEKDDVKLIEVPVEYIAGKVVAKD
YIDESTGELICAANMELSLDLLAKLSQSGHKRIETLFTNDLDHGPYISETLRVDPTNDRL
SALVEIYRMMRPGEPPTREAAESLFENLFFSEDRYDLSAVGRMKFNRSLLREEIEGSGIL
SKDDIIDVMKKLIDIRNGKGEVDDIDHLGNRRIRSVGEMAENQFRVGLVRVERAVKERLS
LGDLDTLMPQDMINAKPISAAVKEFFGSSQLSQFMDQNNPLSEITHKRRISALGPGGLTR
ERAGFEVRDVHPTHYGRVCPIETPEGPNIGLINSLSVYAQTNEYGFLETPYRKVTDGVVT
DEIHYLSAIEEGNYVIAQANSNLDEEGHFVEDLVTCRSKGESSLFSRDQVDYMDVSTQQV
VSVGASLIPFLEHDDANRALMGANMQRQAVPTLRADKPLVGTGMERAVAVDSGVTAVAKR
GGVVQYVDASRIVIKVNEDEMYPGEAGIDIYNLTKYTRSNQNTCINQMPCVSLGEPVERG
DVLADGPSTDLGELALGQNMRVAFMPWNGYNFEDSILVSERVVQEDRFTTIHIQELACVS
RDTKLGPEEITADIPNVGEAALSKLDESGIVYIGAEVTGGDILVGKVTPKGETQLTPEEK
LLRAIFGEKASDVKDSSLRVPNGVSGTVIDVQVFTRDGVEKDKRALEIEEMQLKQAKKDL
SEELQILEAGLFSRIRAVLVAGGVEAEKLDKLPRDRWLELGLTDEEKQNQLEQLAEQYDE
LKHEFEKKLEAKRRKITQGDDLAPGVLKIVKVYLAVKRRIQPGDKMAGRHGNKGVISKIN
PIEDMPYDENGTPVDIVLNPLGVPSRMNIGQILETHLGMAAKGIGDKINAMLKQQQEVAK
LREFIQRAYDLGADVRQKVDLSTFSDEEVMRLAENLRKGMPIATPVFDGAKEAEIKELLK
LGDLPTSGQIRLYDGRTGEQFERPVTVGYMYMLKLNHLVDDKMHARSTGSYSLVTQQPLG
GKAQFGGQRFGEMEVWALEAYGAAYTLQEMLTVKSDDVNGRTKMYKNIVDGNHQMEPGMP
ESFNVLLKEIRSLGINIELEDE
Sequence of entity 3 (D), FASTA
>9GDA_3 DNA-directed RNA polymerase subunit beta' (chains D)
MKDLLKFLKAQTKTEEFDAIKIALASPDMIRSWSFGEVKKPETINYRTFKPERDGLFCAR
IFGPVKDYECLCGKYKRLKHRGVICEKCGVEVTQTKVRRERMGHIELASPTAHIWFLKSL
PSRIGLLLDMPLRDIERVLYFESYVVIEGGMTNLERQQILTEEQYLDALEEFGDEFDAKM
GAEAIQALLKSMDLEQECEQLREELNETNSETKRKKLTKRIKLLEAFVQSGNKPEWMILT
VLPVLPPDLRPLVPLDGGRFATSDLNDLYRRVINRNNRLKRLLDLAAPDIIVRNEKRMLQ
EAVDALLDNGRRGRAITGSNKRPLKSLADMIKGKQGRFRQNLLGKRVDYSGRSVITVGPY
LRLHQCGLPKKMALELFKPFIYGKLELRGLATTIKAAKKMVEREEAVVWDILDEVIREHP
VLLNRAPTLHRLGIQAFEPVLIEGKAIQLHPLVCAAYNADFDGDQMAVHVPLTLEAQLEA
RALMMSTNNILSPANGEPIIVPSQDVVLGLYYMTRDCVNAKGEGMVLTGPKEAERLYRSG
LASLHARVKVRITEYEKDANGELVAKTSLKDTTVGRAILWMIVPKGLPYSIVNQALGKKA
ISKMLNTCYRILGLKPTVIFADQIMYTGFAYAARSGASVGIDDMVIPEKKHEIISEAEAE
VAEIQEQFQSGLVTAGERYNKVIDIWAAANDRVSKAMMDNLQTETVINRDGQEEKQVSFN
SIYMMADSGARGSAAQIRQLAGMRGLMAKPDGSIIETPITANFREGLNVLQYFISTHGAR
KGLADTALKTANSGYLTRRLVDVAQDLVVTEDDCGTHEGIMMTPVIEGGDVKEPLRDRVL
GRVTAEDVLKPGTADILVPRNTLLHEQWCDLLEENSVDAVKVRSVVSCDTDFGVCAHCYG
RDLARGHIINKGEAIGVIAAQSIGEPGTQLTMRTFHIGGAASRAAAESSIQVKNKGSIKL
SNVKSVVNSSGKLVITSRNTELKLIDEFGRTKESYKVPYGAVLAKGDGEQVAGGETVANW
DPHTMPVITEVSGFVRFTDMIDGQTITRQTDELTGLSSLVVLDSAERTAGGKDLRPALKI
VDAQGNDVLIPGTDMPAQYFLPGKAIVQLEDGVQISSGDTLARIPQESGGTKDITGGLPR
VADLFEARRPKEPAILAEISGIVSFGKETKGKRRLVITPVDGSDPYEEMIPKWRQLNVFE
GERVERGDVISDGPEAPHDILRLRGVHAVTRYIVNEVQDVYRLQGVKINDKHIEVIVRQM
LRKATIVNAGSSDFLEGEQVEYSRVKIANRELEANGKVGATYSRDLLGITKASLATESFI
SAASFQETTRVLTEAAVAGKRDELRGLKENVIVGRLIPAGTGYAYHQDRMRRRAAGEAPA
APQVTAEDASASLAELLNAGLGGSDNELELEVLFQ
Sequence of entity 4 (E), FASTA
>9GDA_4 DNA-directed RNA polymerase subunit omega (chains E)
MARVTVQDAVEKIGNRFDLVLVAARRARQMQVGGKDPLVPEENDKTTVIALREIEEGLIN
NQILDVRERQEQQEQEAAELQAVTAIAEGRR
Sequence of entity 5 (F), FASTA
>9GDA_5 DNA topoisomerase 1 (chains F)
GPWSHPQFEKGGGSGGGSGGSAWSHPQFEKHMGKALVIVESPAKAKTINKYLGSDYVVKS
SVGHIRDLPTSGSAAKKSADSTSTKTAKKPKKDERGALVNRMGVDPWHNWEAHYEVLPGK
EKVVSELKQLAEKADHIYLATDLDREGEAIAWHLREVIGGDDARYSRVVFNEITKNAIRQ
AFNKPGELNIDRVNAQQARRFMDRVVGYMVSPLLWKKIARGLSAGRVQSVAVRLVVERER
EIKAFVPEEFWEVDASTTTPSGEALALQVTHQNDKPFRPVNKEQTQAAVSLLEKARYSVL
EREDKPTTSKPGAPFITSTLQQAASTRLGFGVKKTMMMAQRLYEAGYITYMRTDSTNLSQ
DAVNMVRGYISDNFGKKYLPESPNQYASKENSQEAHEAIRPSDVNVMAESLKDMEADAQK
LYQLIWRQFVACQMTPAKYDSTTLTVGAGDFRLKARGRILRFDGWTKVMPALRKGDEDRI
LPAVNKGDALTLVELTPAQHFTKPPARFSEASLVKELEKRGIGRPSTYASIISTIQDRGY
VRVENRRFYAEKMGEIVTDRLEENFRELMNYDFTAQMENSLDQVANHEAEWKAVLDHFFS
DFTQQLDKAEKDPEEGGMRPNQMVLTSIDCPTCGRKMGIRTASTGVFLGCSGYALPPKER
CKTTINLVPENEVLNVLEGEDAETNALRAKRRCPKCGTAMDSYLIDPKRKLHVCGNNPTC
DGYEIEEGEFRIKGYDGPIVECEKCGSEMHLKMGRFGKYMACTNEECKNTRKILRNGEVA
PPKEDPVPLPELPCEKSDAYFVLRDGAAGVFLAANTFPKSRETRAPLVEELYRFRDRLPE
KLRYLADAPQQDPEGNKTMVRFSRKTKQQYVSSEKDGKATGWSAFYVDGKWVEGKK
Sequence of entity 6 (N), FASTA
>9GDA_6 non-template DNA strand (chains N)
GGTCAGTACGTCCTATCGATCTTCGGAAGAGATTCAGAG
Sequence of entity 7 (R), FASTA
>9GDA_7 RNA (chains R)
GAGUCCGCGGCGCG
Sequence of entity 8 (T), FASTA
>9GDA_8 template DNA strand (chains T)
CTCTGAATCTCTTCCGACGCGCCGCGGGACGTACTGACC

Ligands and cofactors

IDNameFormulaCopies
MGMagnesium ionMg1
ZNZinc ionZn5

Primary citation

DNA topoisomerase I acts as supercoiling sensor for bacterial transcription elongation. Vidmar, V., Borde, C., Bruno, L. et al. Nat Struct Mol Biol (2026) 33:134-144. DOI 10.1038/s41594-025-01703-5 · PubMed

Other PDB entries of the same protein (UniProt P0A7Z4 (AlphaFold model), which also has an AlphaFold model), best resolution first:

Browse structure collections

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