9QN5: SUMO-activating enzyme subunit 1

Crystal structure of human SUMO E1 with small unit cell parameters in the P1 21 1 space group. Determined by X-ray diffraction at 1.97 Å resolution. Released 8 Apr 2026.

Method: X-ray diffraction
Resolution: 1.97 Å
Organism: Homo sapiens
Chains: 4
Atoms: 13,159
Mol. weight: 225.74 kDa
Ligands: ATP, MG, ZN
Released: 8 Apr 2026

Explore 9QN5 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9QN5 contains 102 α-helices and 66 β-strands across 4 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: 19 helices, 15 β-strands

Element	Residues	Length	Sheet
α-helix	13-18	6
α-helix	20-35	16
β-strand	38-42	5	1
α-helix	46-58	13
β-strand	62-66	5	1
α-helix	69	1
β-strand	70	1	2
α-helix	71-72	2
β-strand	90	1	2
α-helix	93-95	3
α-helix	96-101	6
β-strand	107-111	5	1
α-helix	115-117	3
α-helix	120-123	4
β-strand	128-131	4	1
α-helix	136-148	13
β-strand	152-159	8	1
β-strand	160	1	3
β-strand	162-168	7	1
β-strand	171-176	6	4
β-strand	207-212	6	4
α-helix	216-220	5
α-helix	227-233	7
α-helix	239-253	15
α-helix	259-261	3
α-helix	262-280	19
α-helix	284-286	3
α-helix	289-294	6
β-strand	298	1	3
α-helix	300-319	20
β-strand	321	1	4
α-helix	323-325	3
β-strand	328-332	5	1
β-strand	337-341	5	1

Chain B: 32 helices, 18 β-strands

Element	Residues	Length	Sheet
α-helix	9-17	9
β-strand	19-23	5	1
α-helix	27-39	13
β-strand	43-48	6	1
β-strand	51	1	5
α-helix	54-58	5
α-helix	65-67	3
β-strand	71	1	5
α-helix	72-83	12
β-strand	88-93	6	1
α-helix	103-106	4
β-strand	111-114	4	1
α-helix	119-132	14
β-strand	136-142	7	1
β-strand	145-151	7	1
α-helix	163-171	9
α-helix	172-176	5
α-helix	182-197	16
α-helix	202-204	3
α-helix	213-215	3
α-helix	240-246	7
α-helix	251-256	6
α-helix	257-261	5
α-helix	262-267	6
α-helix	270-273	4
α-helix	277-279	3
α-helix	284-288	5
α-helix	308-310	3
α-helix	315-336	22
α-helix	349-365	17
α-helix	368-370	3
α-helix	373-381	9
α-helix	383-385	3
α-helix	388-405	18
α-helix	410-412	3
β-strand	414-418	5	1
β-strand	427-433	7	1
α-helix	434-438	5
β-strand	449-454	6	6
β-strand	460	1	7
α-helix	461-463	3
α-helix	464-472	9
β-strand	479-482	4	6
β-strand	489-491	3	6
α-helix	499-501	3
β-strand	505	1	7
α-helix	506-509	4
β-strand	516-521	6	6
β-strand	526-534	9	6
β-strand	544-546	3	6

Chain C: 19 helices, 15 β-strands

Element	Residues	Length	Sheet
α-helix	13-18	6
α-helix	20-26	7
α-helix	28-35	8
β-strand	38-42	5	8
α-helix	46-58	13
β-strand	62-66	5	8
β-strand	70	1	9
α-helix	83	1
β-strand	90	1	9
α-helix	91-102	12
β-strand	107-111	5	8
α-helix	115-117	3
α-helix	120-123	4
β-strand	128-131	4	8
α-helix	136-148	13
β-strand	152-159	8	8
β-strand	160	1	10
β-strand	162-168	7	8
β-strand	171-177	7	11
β-strand	206-212	7	11
α-helix	216-220	5
α-helix	227-232	6
α-helix	233-235	3
α-helix	239-253	15
α-helix	259-261	3
α-helix	262-278	17
α-helix	284-286	3
α-helix	289-294	6
β-strand	298	1	10
α-helix	300-319	20
β-strand	321	1	11
α-helix	323-325	3
β-strand	328-332	5	8
β-strand	337-341	5	8

Chain D: 32 helices, 18 β-strands

Element	Residues	Length	Sheet
α-helix	9-17	9
β-strand	20-23	4	8
α-helix	27-39	13
β-strand	43-48	6	8
α-helix	50	1
β-strand	51	1	12
α-helix	52-53	2
α-helix	65-67	3
β-strand	71	1	12
α-helix	72-83	12
β-strand	88-93	6	8
α-helix	103-107	5
β-strand	111-114	4	8
α-helix	119-132	14
β-strand	136-142	7	8
β-strand	145-151	7	8
α-helix	166-169	4
α-helix	172-176	5
α-helix	182-197	16
α-helix	202-204	3
α-helix	213-215	3
α-helix	219-223	5
α-helix	245-247	3
α-helix	251-256	6
α-helix	257-261	5
α-helix	262-267	6
α-helix	270-273	4
α-helix	277-281	5
α-helix	284-287	4
α-helix	308-310	3
α-helix	315-334	20
α-helix	349-365	17
α-helix	368-370	3
α-helix	373-380	8
α-helix	388-405	18
β-strand	414-418	5	8
β-strand	427-433	7	8
α-helix	434-437	4
β-strand	449-454	6	13
β-strand	460	1	14
α-helix	461-463	3
α-helix	464-472	9
β-strand	479-482	4	13
β-strand	489-491	3	13
α-helix	495-497	3
β-strand	505	1	14
α-helix	506-509	4
β-strand	516-521	6	13
β-strand	526-534	9	13
β-strand	544-546	3	13

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
SUMO-activating enzyme subunit 1	A, C	protein	369	Homo sapiens	Q9UBE0 (AlphaFold model)
SUMO-activating enzyme subunit 2	B, D	protein	640	Homo sapiens	Q9UBT2 (AlphaFold model)

Sequence of entity 1 (A, C), FASTA

>9QN5_1 SUMO-activating enzyme subunit 1 (chains A, C)
MGSSHHHHHHSSGLVPRGSHMASMVEKEEAGGGISEEEAAQYDRQIRLWGLEAQKRLRAS
RVLLVGLKGLGAEIAKNLILAGVKGLTMLDHEQVTPEDPGAQFLIRTGSVGRNRAEASLE
RAQNLNPMVDVKVDTEDIEKKPESFFTQFDAVCLTCCSRDVIVKVDQICHKNSIKFFTGD
VFGYHGYTFANLGEHEFVEEKTKVAKVSQGVEDGPDTKRAKLDSSETTMVKKKVVFCPVK
EALEVDWSSEKAKAALKRTTSDYFLLQVLLKFRTDKGRDPSSDTYEEDSELLLQIRNDVL
DSLGISPDLLPEDFVRYCFSEMAPVCAVVGGILAQEIVKALSQRDPPHNNFFFFDGMKGN
GIVECLGPK

Sequence of entity 2 (B, D), FASTA

>9QN5_2 SUMO-activating enzyme subunit 2 (chains B, D)
MALSRGLPRELAEAVAGGRVLVVGAGGIGCELLKNLVLTGFSHIDLIDLDTIDVSNLNRQ
FLFQKKHVGRSKAQVAKESVLQFYPKANIVAYHDSIMNPDYNVEFFRQFILVMNALDNRA
ARNHVNRMCLAADVPLIESGTAGYLGQVTTIKKGVTECYECHPKPTQRTFPGCTIRNTPS
EPIHCIVWAKYLFNQLFGEEDADQEVSPDRADPEAAWEPTEAEARARASNEDGDIKRIST
KEWAKSTGYDPVKLFTKLFKDDIRYLLTMDKLWRKRKPPVPLDWAEVQSQGEETNASDQQ
NEPQLGLKDQQVLDVKSYARLFSKSIETLRVHLAEKGDGAELIWDKDDPSAMDFVTSAAN
LRMHIFSMNMKSRFDIKSMAGNIIPAIATTNAVIAGLIVLEGLKILSGKIDQCRTIFLNK
QPNPRKKLLVPCALDPPNPNCYVCASKPEVTVRLNVHKVTVLTLQDKIVKEKFAMVAPDV
QIEDGKGTILISSEEGETEANNHKKLSEFGIRNGSRLQADDFLQDYTLLINILHSEDLGK
DVEFEVVGDAPEKVGPKQAEDAAKSITNGSDDGAQPSTSTAQEQDDVLIVDSDEEDSSNN
ADVSEEERSRKRKLDEKENLSAKRSRIEQKEELDDVIALD

Ligands and cofactors

ID	Name	Formula	Copies
ATP	Adenosine-5'-triphosphate	C10 H16 N5 O13 P3	2
MG	Magnesium ion	Mg	2
ZN	Zinc ion	Zn	2

Primary citation

Crystal unit cell dynamics revealed by SUMO E1 conformational flexibility. Viloria, M., Francois, R.M.M., Didierjean, C. To be published.

Other PDB entries of the same protein (UniProt Q9UBE0 (AlphaFold model), which also has an AlphaFold model), best resolution first:

6XOG 1.98 Å, Structure of SUMO1-ML786519 adduct bound to SAE
6XOI 2.0 Å, Structure of SUMO1-ML00752641 adduct bound to SAE
8VY5 2.01 Å, Crystal structure of human SAE1
6XOH 2.23 Å, Structure of SUMO1-ML00789344 adduct bound to SAE
1Y8Q 2.25 Å, Sumo E1 activating enzyme SAE1-SAE2-MG-ATP complex
3KYC 2.45 Å, Human SUMO E1 complex with a SUMO1-AMP mimic
6CWY 2.46 Å, Crystal structure of SUMO E1 in complex with an allosteric inhibitor
9IF6 2.51 Å, Crystal structure of human SUMO E1 with large unit cell parameters in the P1 21 1 space…
3KYD 2.61 Å, Human SUMO E1~SUMO1-AMP tetrahedral intermediate mimic
9DRJ 2.7 Å, Cryo-EM structure of a SUMO E1-E2-SUMO1 complex.
1Y8R 2.75 Å, Sumo E1 activating enzyme SAE1-SAE2-SUMO1-MG-ATP complex
6CWZ 3.1 Å, Crystal structure of apo SUMO E1

Browse structure collections

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