9QK2: Complement C4-A

Structure of the Complement classical and lectin pathway C3 convertase in complex with substrate C3. Determined by electron microscopy at 3.5 Å resolution. Released 24 Dec 2025.

Method: Electron microscopy
Resolution: 3.5 Å
Organisms: Homo sapiens, Lama glama
Chains: 7
Atoms: 29,917
Mol. weight: 1052.22 kDa
Ligands: MG, NAG
Released: 24 Dec 2025

Explore 9QK2 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9QK2 contains 112 α-helices and 266 β-strands across 7 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: 15 helices, 53 β-strands

Element	Residues	Length	Sheet
β-strand	22-26	5	1
β-strand	30-32	3	2
β-strand	37-44	8	1
β-strand	52-59	8	3
β-strand	72-76	5	3
β-strand	82-87	6	1
α-helix	91-96	6
α-helix	99-101	3
β-strand	109-113	5	3
α-helix	115-116	2
α-helix	117-121	5
β-strand	127-131	5	3
β-strand	133-135	3	2
β-strand	140-145	6	4
β-strand	149-150	2	5
β-strand	155-163	9	4
β-strand	169	1	4
β-strand	174-179	6	5
β-strand	185-188	4	5
β-strand	197-203	7	4
α-helix	208-209	2
β-strand	211-219	9	5
β-strand	227-233	7	5
β-strand	241-247	7	6
β-strand	251-253	3	7
β-strand	262-270	9	6
β-strand	275	1	6
β-strand	278-287	10	7
β-strand	293-295	3	7
β-strand	301-304	4	7
β-strand	306	1	6
β-strand	309-314	6	6
α-helix	316-325	10
α-helix	330-332	3
β-strand	337-346	10	7
β-strand	352-357	6	7
β-strand	361-363	3	7
β-strand	367-368	2	8
α-helix	378-379	2
β-strand	384-389	6	9
β-strand	391-392	2	8
β-strand	397	1	8
α-helix	398	1
β-strand	402-409	8	10
β-strand	417-424	8	10
β-strand	430-435	6	9
β-strand	443-450	8	10
β-strand	456-463	8	10
α-helix	464-466	3
β-strand	472-476	5	11
β-strand	488-496	9	11
β-strand	504-511	8	12
β-strand	514-522	9	12
β-strand	527-532	6	11
β-strand	540-548	9	12
β-strand	553-556	4	12
β-strand	559-561	3	12
α-helix	562-564	3
β-strand	574	1	13
β-strand	586-591	6	13
β-strand	596-600	5	14
β-strand	601-604	4	15
α-helix	607-611	5
α-helix	621-629	9
α-helix	643-650	8
β-strand	655	1	16
β-strand	660	1	16
α-helix	661-664	4

Chain B: 19 helices, 35 β-strands

Element	Residues	Length	Sheet
β-strand	766	1	31
α-helix	773	1
β-strand	774-775	2	32
β-strand	781-782	2	15
β-strand	786-790	5	14
β-strand	793-798	6	13
β-strand	805-810	6	15
β-strand	813-814	2	14
β-strand	818-819	2	14
β-strand	825-828	4	15
β-strand	833-836	4	33
β-strand	843-844	2	34
β-strand	849-851	3	35
β-strand	854-857	4	33
β-strand	865-869	5	32
β-strand	875-876	2	36
β-strand	885-887	3	32
β-strand	893-896	4	33
β-strand	899-901	3	35
β-strand	902-903	2	36
β-strand	908-917	10	32
β-strand	918	1	31
β-strand	924-932	9	32
β-strand	933-934	2	34
α-helix	935	1
β-strand	938-948	11	5
α-helix	954-956	3
β-strand	957-960	4	37
β-strand	968	1	5
β-strand	975-981	7	5
α-helix	982-983	2
α-helix	997-1001	5
α-helix	1013-1031	19
α-helix	1034-1036	3
α-helix	1039-1055	17
α-helix	1056-1058	3
α-helix	1076-1088	13
α-helix	1097-1109	13
α-helix	1127-1132	6
α-helix	1138-1154	17
α-helix	1162-1185	24
α-helix	1190-1202	13
α-helix	1207-1219	13
α-helix	1259-1274	16
α-helix	1282-1293	12
α-helix	1302-1319	18
β-strand	1327-1334	8	37
β-strand	1339-1344	6	37
β-strand	1355-1360	6	5
β-strand	1366-1372	7	37
β-strand	1376-1386	11	5
β-strand	1397-1401	5	18
β-strand	1404-1405	2	17
β-strand	1409	1	20

Chain C: 4 helices, 23 β-strands

Element	Residues	Length	Sheet
β-strand	1465-1467	3	17
β-strand	1470-1474	5	18
β-strand	1484-1489	6	19
β-strand	1494-1496	3	17
α-helix	1498-1505	8
β-strand	1514-1518	5	19
β-strand	1521-1526	6	19
β-strand	1535-1536	2	18
β-strand	1539-1542	4	17
β-strand	1546	1	20
β-strand	1552-1558	7	19
β-strand	1565-1570	6	19
β-strand	1581	1	21
β-strand	1584	1	22
β-strand	1587	1	22
β-strand	1590	1	21
α-helix	1614-1618	5
β-strand	1625-1637	13	23
β-strand	1640-1652	13	23
β-strand	1663-1670	8	23
β-strand	1682-1687	6	23
β-strand	1692-1693	2	24
β-strand	1699-1700	2	24
β-strand	1701-1702	2	23
β-strand	1708-1711	4	23
α-helix	1712-1713	2
α-helix	1721-1739	19

Chain D: 1 helix, 11 β-strands

Element	Residues	Length	Sheet
β-strand	4-7	4	38
β-strand	13	1	39
β-strand	19-24	6	38
β-strand	31-35	5	40
β-strand	42-47	6	40
β-strand	54-56	3	40
α-helix	58-60	3
β-strand	65-68	4	38
β-strand	74-78	5	38
β-strand	88-93	6	40
β-strand	114-116	3	40
β-strand	119	1	39

Chain E: 16 helices, 25 β-strands

Element	Residues	Length	Sheet
β-strand	245-246	2	25
β-strand	252-260	9	26
α-helix	267-286	20
β-strand	291-298	8	26
β-strand	302-306	5	26
α-helix	311-314	4
α-helix	316-324	9
α-helix	329-331	3
α-helix	339-355	17
α-helix	362-365	4
β-strand	367-374	8	26
α-helix	385-395	11
α-helix	403-405	3
β-strand	406-412	7	26
α-helix	420-426	7
β-strand	436-438	3	26
α-helix	442-451	10
β-strand	453-454	2	25
α-helix	474-477	4
β-strand	481-485	5	27
β-strand	492-496	5	27
β-strand	501-504	4	27
β-strand	519-522	4	27
β-strand	531-540	10	27
β-strand	563-567	5	27
β-strand	574	1	28
β-strand	577	1	28
β-strand	581	1	29
β-strand	585	1	30
α-helix	586-591	6
α-helix	600-607	8
β-strand	612-618	7	29
β-strand	624-630	7	29
α-helix	633-644	12
β-strand	663-664	2	29
β-strand	682-687	6	29
β-strand	690-699	10	29
β-strand	728-730	3	29
α-helix	733-735	3
α-helix	736-743	8
β-strand	749	1	30

Chain F: 15 helices, 62 β-strands

Element	Residues	Length	Sheet
β-strand	25-31	7	41
β-strand	33-34	2	42
β-strand	36	1	43
β-strand	39-47	9	41
β-strand	53-61	9	42
β-strand	68-76	9	42
α-helix	78-80	3
β-strand	83-89	7	41
β-strand	90	1	43
β-strand	105-112	8	42
β-strand	115-123	9	42
β-strand	129-134	6	44
β-strand	138	1	45
α-helix	143	1
β-strand	144-152	9	44
β-strand	158	1	44
β-strand	162-168	7	45
β-strand	174-181	8	45
β-strand	188-194	7	44
β-strand	203-210	8	45
β-strand	218-223	6	45
β-strand	232-238	7	46
β-strand	243-244	2	47
β-strand	251-259	9	46
β-strand	264	1	46
β-strand	267-276	10	48
β-strand	277	1	49
β-strand	280	1	49
β-strand	283	1	48
β-strand	289-293	5	48
β-strand	294	1	46
β-strand	297	1	46
β-strand	300-302	3	46
α-helix	304-310	7
α-helix	316-319	4
β-strand	323-332	10	48
β-strand	338-346	9	48
β-strand	348-349	2	47
β-strand	354-357	4	50
β-strand	363-364	2	51
β-strand	370-371	2	52
β-strand	374-377	4	50
β-strand	383	1	50
β-strand	388-391	4	53
β-strand	399-400	2	53
β-strand	406-407	2	50
β-strand	410-411	2	52
α-helix	412-414	3
α-helix	419	1
β-strand	420-426	7	53
α-helix	433-435	3
β-strand	438-443	6	53
β-strand	444-445	2	51
β-strand	455-459	5	54
β-strand	465	1	55
β-strand	470-478	9	54
α-helix	484-486	3
β-strand	489-490	2	56
β-strand	491-496	6	57
β-strand	499-503	5	57
β-strand	506-507	2	56
β-strand	514-520	7	54
α-helix	523-525	3
β-strand	529-538	10	57
β-strand	544-553	10	57
β-strand	555	1	55
β-strand	563-567	5	58
β-strand	580-588	9	58
β-strand	592-598	7	59
α-helix	601-605	5
α-helix	606-608	3
α-helix	613-621	9
α-helix	635-641	7
β-strand	644-648	5	41
β-strand	653	1	41
α-helix	654-656	3
α-helix	662-664	3

Chain G: 42 helices, 57 β-strands

Element	Residues	Length	Sheet
α-helix	676-683	8
α-helix	688-698	11
α-helix	700-701	2
α-helix	707-710	4
α-helix	711-713	3
α-helix	718-741	24
α-helix	750-752	3
α-helix	768-770	3
β-strand	771	1	59
β-strand	775-777	3	59
α-helix	781-782	2
β-strand	783	1	58
β-strand	786-794	9	58
β-strand	801-810	10	59
β-strand	814-817	4	59
α-helix	818-820	3
β-strand	821-824	4	59
β-strand	829-834	6	60
β-strand	838-840	3	61
β-strand	844-845	2	62
β-strand	848-853	6	60
β-strand	860-866	7	61
β-strand	869	1	63
β-strand	872	1	63
β-strand	882-888	7	61
α-helix	889	1
β-strand	892-897	6	60
β-strand	900	1	62
β-strand	902	1	63
β-strand	906-916	11	61
β-strand	924-932	9	61
β-strand	936-943	8	64
β-strand	946-947	2	64
β-strand	958-962	5	65
α-helix	963-965	3
β-strand	970	1	64
α-helix	971	1
β-strand	977-983	7	64
α-helix	988-995	8
α-helix	1000-1003	4
α-helix	1013-1015	3
α-helix	1019-1031	13
α-helix	1034-1037	4
α-helix	1040-1056	17
α-helix	1057-1059	3
β-strand	1060	1	66
β-strand	1066	1	66
β-strand	1067	1	67
β-strand	1074	1	67
α-helix	1076-1087	12
α-helix	1097-1110	14
β-strand	1112	1	68
β-strand	1118	1	68
α-helix	1123-1124	2
α-helix	1140-1153	14
α-helix	1165-1178	14
α-helix	1180-1182	3
α-helix	1186-1199	14
α-helix	1205-1213	9
β-strand	1215	1	69
β-strand	1219	1	69
α-helix	1227-1242	16
α-helix	1249-1256	8
β-strand	1262	1	70
β-strand	1265	1	70
α-helix	1269-1284	16
β-strand	1293-1299	7	65
α-helix	1306	1
β-strand	1307-1312	6	65
β-strand	1319-1324	6	64
β-strand	1330-1334	5	65
β-strand	1340-1350	11	64
β-strand	1361-1369	9	71
β-strand	1382-1392	11	71
β-strand	1401-1406	6	72
β-strand	1411-1413	3	71
α-helix	1415-1423	9
β-strand	1431-1433	3	72
β-strand	1443-1448	6	72
β-strand	1457-1465	9	71
β-strand	1469-1470	2	62
α-helix	1472-1474	3
β-strand	1475-1481	7	72
β-strand	1488-1493	6	72
α-helix	1510-1515	6
α-helix	1529-1536	8
β-strand	1541-1553	13	73
β-strand	1558-1570	13	73
β-strand	1581-1587	7	73
α-helix	1588-1590	3
α-helix	1591-1594	4
β-strand	1601-1607	7	73
β-strand	1611	1	73
β-strand	1620-1621	2	73
β-strand	1629-1631	3	73
α-helix	1632-1633	2
α-helix	1635-1638	4
α-helix	1640-1654	15
α-helix	1655-1659	5

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Complement C4-A	A, B, C	protein	1744	Homo sapiens	P0C0L4 (AlphaFold model)
Complement C2	E	protein	752	Homo sapiens	P06681 (AlphaFold model)
Anti-C4b nanobody B12	D	protein	120	Lama glama
Complement C3	F, G	protein	1663	Homo sapiens	P01024 (AlphaFold model)

Sequence of entity 1 (A, B, C), FASTA

>9QK2_1 Complement C4-A (chains A, B, C)
MRLLWGLIWASSFFTLSLQKPRLLLFSPSVVHLGVPLSVGVQLQDVPRGQVVKGSVFLRN
PSRNNVPCSPKVDFTLSSERDFALLSLQVPLKDAKSCGLHQLLRGPEVQLVAHSPWLKDS
LSRTTNIQGINLLFSSRRGHLFLQTDQPIYNPGQRVRYRVFALDQKMRPSTDTITVMVEN
SHGLRVRKKEVYMPSSIFQDDFVIPDISEPGTWKISARFSDGLESNSSTQFEVKKYVLPN
FEVKITPGKPYILTVPGHLDEMQLDIQARYIYGKPVQGVAYVRFGLLDEDGKKTFFRGLE
SQTKLVNGQSHISLSKAEFQDALEKLNMGITDLQGLRLYVAAAIIESPGGEMEEAELTSW
YFVSSPFSLDLSKTKRHLVPGAPFLLQALVREMSGSPASGIPVKVSATVSSPGSVPEVQD
IQQNTDGSGQVSIPIIIPQTISELQLSVSAGSPHPAIARLTVAAPPSGGPGFLSIERPDS
RPPRVGDTLNLNLRAVGSGATFSHYYYMILSRGQIVFMNREPKRTLTSVSVFVDHHLAPS
FYFVAFYYHGDHPVANSLRVDVQAGACEGKLELSVDGAKQYRNGESVKLHLETDSLALVA
LGALDTALYAAGSKSHKPLNMGKVFEAMNSYDLGCGPGGGDSALQVFQAAGLAFSDGDQW
TLSRKRLSCPKEKTTRKKRNVNFQKAINEKLGQYASPTAKRCCQDGVTRLPMMRSCEQRA
ARVQQPDCREPFLSCCQFAESLRKKSRDKGQAGLQRALEILQEEDLIDEDDIPVRSFFPE
NWLWRVETVDRFQILTLWLPDSLTTWEIHGLSLSKTKGLCVATPVQLRVFREFHLHLRLP
MSVRRFEQLELRPVLYNYLDKNLTVSVHVSPVEGLCLAGGGGLAQQVLVPAGSARPVAFS
VVPTAAAAVSLKVVARGSFEFPVGDAVSKVLQIEKEGAIHREELVYELNPLDHRGRTLEI
PGNSDPNMIPDGDFNSYVRVTASDPLDTLGSEGALSPGGVASLLRLPRGCGEQTMIYLAP
TLAASRYLDKTEQWSTLPPETKDHAVDLIQKGYMRIQQFRKADGSYAAWLSRDSSTWLTA
FVLKVLSLAQEQVGGSPEKLQETSNWLLSQQQADGSFQDPCPVLDRSMQGGLVGNDETVA
LTAFVTIALHHGLAVFQDEGAEPLKQRVEASISKANSFLGEKASAGLLGAHAAAITAYAL
SLTKAPVDLLGVAHNNLMAMAQETGDNLYWGSVTGSQSNAVSPTPAPRNPSDPMPQAPAL
WIETTAYALLHLLLHEGKAEMADQASAWLTRQGSFQGGFRSTQDTVIALDALSAYWIASH
TTEERGLNVTLSSTGRNGFKSHALQLNNRQIRGLEEELQFSLGSKINVKVGGNSKGTLKV
LRTYNVLDMKNTTCQDLQIEVTVKGHVEYTMEANEDYEDYEYDELPAKDDPDAPLQPVTP
LQLFEGRRNRRRREAPKVVEEQESRVHYTVCIWRNGKVGLSGMAIADVTLLSGFHALRAD
LEKLTSLSDRYVSHFETEGPHVLLYFDSVPTSRECVGFEAVQEVPVGLVQPASATLYDYY
NPERRCSVFYGAPSKSRLLATLCSAEVCQCAEGKCPRQRRALERGLQDEDGYRMKFACYY
PRVEYGFQVKVLREDSRAAFRLFETKITQVLHFTKDVKAAANQMRNFLVRASCRLRLEPG
KEYLIMGLDGATYDLEGHPQYLLDSNSWIEEMPSERLCRSTRQRAACAQLNDFLQEYGTQ
GCQV

Sequence of entity 2 (E), FASTA

>9QK2_2 Complement C2 (chains E)
MGPLMVLFCLLFLYPGLADSAPSCPQNVNISGGTFTLSHGWAPGSLLTYSCPQGLYPSPA
SRLCKSSGQWQTPGATRSLSKAVCKPVRCPAPVSFENGIYTPRLGSYPVGGNVSFECEDG
FILRGSPVRQCRPNGMWDGETAVCDNGAGHCPNPGISLGAVRTGFRFGHGDKVRYRCSSN
LVLTGSSERECQGNGVWSGTEPICRQPYSYDFPEDVAPALGTSFSHMLGATNPTQKTKES
LGRKIQIQRSGHLNLYLLLDCSQSVSENDFLIFKESASLMVDRIFSFEINVSVAIITFAS
EPKVLMSVLNDNSRDMTEVISSLENANYKDHENGTGTNTYAALNSVYLMMNNQMRLLGME
TMAWQEIRHAIILLTDGKSNMGGSPKTAVDHIREILNINQKRNDYLDIYAIGVGKLDVDW
RELNELGSKKDGERHAFILQDTKALHQVFEHMLDVSKLTDTICGVGNMSANASDQERTPW
HVTIKPKSQETCRGALISDQWVLTAAHCFRDGNDHSLWRVNVGDPKSQWGKEFLIEKAVI
SPGFDVFAKKNQGILEFYGDDIALLKLAQKVKMSTHARPICLPCTMEANLALRRPQGSTC
RDHENELLNKQSVPAHFVALNGSKLNINLKMGVEWTSCAEVVSQEKTMFPNLTDVREVVT
DQFLCSGTQEDESPCKGEAGGAVFLERRFRFFQVGLVSWGLYNPCLGSADKNSRKRAPRS
KVPPPRDFHINLFRMQPWLRQHLGDVLNFLPL

Sequence of entity 3 (D), FASTA

>9QK2_3 Anti-C4b nanobody B12 (chains D)
EVQLVESGGGLVQAGGSLRLSCVASERTYMAWFRQAPGKEREFVAAITSSGMMTEYAPSV
KGRFTISRDNAKNTVYLQMNSLKPEDTAVYYCAADLRQRFGERVTEYDYWGQGTQVTVSS

Sequence of entity 4 (F, G), FASTA

>9QK2_4 Complement C3 (chains F, G)
MGPTSGPSLLLLLLTHLPLALGSPMYSIITPNILRLESEETMVLEAHDAQGDVPVTVTVH
DFPGKKLVLSSEKTVLTPATNHMGNVTFTIPANREFKSEKGRNKFVTVQATFGTQVVEKV
VLVSLQSGYLFIQTDKTIYTPGSTVLYRIFTVNHKLLPVGRTVMVNIENPEGIPVKQDSL
SSQNQLGVLPLSWDIPELVNMGQWKIRAYYENSPQQVFSTEFEVKEYVLPSFEVIVEPTE
KFYYIYNEKGLEVTITARFLYGKKVEGTAFVIFGIQDGEQRISLPESLKRIPIEDGSGEV
VLSRKVLLDGVQNLRAEDLVGKSLYVSATVILHSGSDMVQAERSGIPIVTSPYQIHFTKT
PKYFKPGMPFDLMVFVTNPDGSPAYRVPVAVQGEDTVQSLTQGDGVAKLSINTHPSQKPL
SITVRTKKQELSEAEQATRTMQALPYSTVGNSNNYLHLSVLRTELRPGETLNVNFLLRMD
RAHEAKIRYYTYLIMNKGRLLKAGRQVREPGQDLVVLPLSITTDFIPSFRLVAYYTLIGA
SGQREVVADSVWVDVKDSCVGSLVVKSGQSEDRQPVPGQQMTLKIEGDHGARVVLVAVDK
GVFVLNKKNKLTQSKIWDVVEKADIGCTPGSGKDYAGVFSDAGLTFTSSSGQQTAQRAEL
QCPQPAARRRRSVQLTEKRMDKVGKYPKELRKCCEDGMRENPMRFSCQRRTRFISLGEAC
KKVFLDCCNYITELRRQHARASHLGLARSNLDEDIIAEENIVSRSEFPESWLWNVEDLKE
PPKNGISTKLMNIFLKDSITTWEILAVSMSDKKGICVADPFEVTVMQDFFIDLRLPYSVV
RNEQVEIRAVLYNYRQNQELKVRVELLHNPAFCSLATTKRRHQQTVTIPPKSSLSVPYVI
VPLKTGLQEVEVKAAVYHHFISDGVRKSLKVVPEGIRMNKTVAVRTLDPERLGREGVQKE
DIPPADLSDQVPDTESETRILLQGTPVAQMTEDAVDAERLKHLIVTPSGCGEQNMIGMTP
TVIAVHYLDETEQWEKFGLEKRQGALELIKKGYTQQLAFRQPSSAFAAFVKRAPSTWLTA
YVVKVFSLAVNLIAIDSQVLCGAVKWLILEKQKPDGVFQEDAPVIHQEMIGGLRNNNEKD
MALTAFVLISLQEAKDICEEQVNSLPGSITKAGDFLEANYMNLQRSYTVAIAGYALAQMG
RLKGPLLNKFLTTAKDKNRWEDPGKQLYNVEATSYALLALLQLKDFDFVPPVVRWLNEQR
YYGGGYGSTQATFMVFQALAQYQKDAPDHQELNLDVSLQLPSRSSKITHRIHWESASLLR
SEETKENEGFTVTAEGKGQGTLSVVTMYHAKAKDQLTCNKFDLKVTIKPAPETEKRPQDA
KNTMILEICTRYRGDQDATMSILDISMMTGFAPDTDDLKQLANGVDRYISKYELDKAFSD
RNTLIIYLDKVSHSEDDCLAFKVHQYFNVELIQPGAVKVYAYYNLEESCTRFYHPEKEDG
KLNKLCRDELCRCAEENCFIQKSDDKVTLEERLDKACEPGVDYVYKTRLVKVQLSNDFDE
YIMAIEQTIKSGSDEVQVGQQRTFISPIKCREALKLEEKKHYLMWGLSSDFWGEKPNLSY
IIGKDTWVEHWPEEDECQDEENQKQCQDLGAFTESMVVFGCPN

Ligands and cofactors

ID	Name	Formula	Copies
MG	Magnesium ion	Mg	1
NAG	2-acetamido-2-deoxy-beta-D-glucopyranose	C8 H15 N O6	8

Primary citation

Structural insights into C3 convertase activity of the classical pathway of complement. De la O Becerra, K.I., Brondijk, T.H.C., Serna Martin, I. et al. Nat Commun (2025) 17:993-993. DOI 10.1038/s41467-025-67730-4 · PubMed

Other PDB entries of the same protein (UniProt P0C0L4 (AlphaFold model), which also has an AlphaFold model), best resolution first:

1HZF 2.3 Å, C4ADG fragment of human complement factor C4A
6YSQ 3.3 Å, The hC4Nb8 complement inhibitory nanobody in complex with C4b
7B2M 3.39 Å, Cryo-EM structure of complement C4b in complex with nanobody E3
7B2P 3.43 Å, Cryo-EM structure of complement C4b in complex with nanobody B5
5JTW 3.5 Å, Crystal structure of complement C4b re-refined using iMDFF
9QJ5 3.5 Å, Structure of the Complement classical and lectin pathway proconvertase, C4b2
5JPN 3.6 Å, Structure of human complement C4 rebuilt using iMDFF
5JPM 3.75 Å, Structure of the complex of human complement C4 with MASP-2 rebuilt using iMDFF
7B2Q 3.76 Å, Cryo-EM structure of complement C4b in complex with nanobody B12
9QJ4 3.9 Å, Structure of the Complement classical and lectin pathway proconvertase, C4b2
9QPY 4.3 Å, Structure of the Complement classical and lectin pathway C3 convertase

Browse structure collections

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