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Protein Structures and Oligomeric States

Enter a protein name, UniProt accession or PDB ID. Name searches ask you to confirm the protein identity before related structures are queried.

Current Protein Identity：P22515 New Search
13PDB entries
30Biological assembly
31chain/assembly records
Main Difference Dimensions in This Set
Different construct Different mutation/modification Different assembly state Different ligand/ion Different experimental conditions Different structure-quality metrics

Difference tags compare only the current result set; every original PDB and assembly record remains separate.

Related-Structure Differences

Each row represents one biological assembly in one PDB entry; multiple monomers of the same protein are listed separately.

PDB Entry Assembly / Oligomeric State Construct Mutations and Modifications Ligands, Ions and Non-polymers Experimental Method Experimental Conditions Structure Quality
3CMM Crystal Structure of the Uba1-Ubiquitin Complex Deposited 2008-03-23 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 10–1024（1015 aa） Fragment：Residues 10-1024
Not recorded PRO PROLINE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 7.6；298 K；L-proline, PEG 5000 MME, pH 7.6, VAPOR DIFFUSION, HANGING DROP, temperature 298K
Resolution 2.70 Å R-free 0.247
3CMM Crystal Structure of the Uba1-Ubiquitin Complex Deposited 2008-03-23 Assembly 2 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain C 10–1024（1015 aa） Fragment：Residues 10-1024
Not recorded PRO PROLINE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 7.6；298 K；L-proline, PEG 5000 MME, pH 7.6, VAPOR DIFFUSION, HANGING DROP, temperature 298K
Resolution 2.70 Å R-free 0.247
4NNJ Crystal structure of Uba1 in complex with ubiquitin-AMP and thioesterified ubiquitin Deposited 2013-11-18 Assembly 1 Protein heterocomplex Heteromer；Protein × 5 PDB declaration: pentameric（5） Consistent with protein count
Chain A 9–1024（1016 aa） Fragment：UNP residues 9-1024
Chain C 9–1024（1016 aa） Fragment：UNP residues 9-1024
Not recorded SO4 SULFATE ION × 4 GOL GLYCEROL × 29 AMP ADENOSINE MONOPHOSPHATE × 2 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 6；298 K；15% (w/v) polyethylene glycol 3350, 100mM lithium sulfate and 100mM BisTris, pH 6.0, VAPOR DIFFUSION, HANGING DROP, temperature 298K
Resolution 2.40 Å R-free 0.201
5L6H Uba1 in complex with Ub-ABPA3 covalent adduct Deposited 2016-05-30 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 1–1024（1024 aa）
Non-standard monomer：Yes (specific site not provided by mmCIF) SO4 SULFATE ION × 1 CL CHLORIDE ION × 4 GOL GLYCEROL × 7 6O2 [(2~{R},3~{S},4~{R},5~{R})-5-[6-[(3-ethynylphenyl)amino]purin-9-yl]-3,4-bis(oxidanyl)oxolan-2-yl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6；293 K；0.2M lithium sulfate, 0.1M bis-tris, 15% peg 3350
Resolution 2.30 Å R-free 0.218
5L6H Uba1 in complex with Ub-ABPA3 covalent adduct Deposited 2016-05-30 Assembly 2 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain C 1–1024（1024 aa）
Non-standard monomer：Yes (specific site not provided by mmCIF) SO4 SULFATE ION × 1 CL CHLORIDE ION × 4 GOL GLYCEROL × 4 6O2 [(2~{R},3~{S},4~{R},5~{R})-5-[6-[(3-ethynylphenyl)amino]purin-9-yl]-3,4-bis(oxidanyl)oxolan-2-yl]methyl sulfamate × 1 MG MAGNESIUM ION × 1 ACT ACETATE ION × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6；293 K；0.2M lithium sulfate, 0.1M bis-tris, 15% peg 3350
Resolution 2.30 Å R-free 0.218
5L6I Uba1 in complex with Ub-MLN4924 covalent adduct Deposited 2016-05-30 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 1–1024（1024 aa）
Non-standard monomer：Yes (specific site not provided by mmCIF) SO4 SULFATE ION × 1 CL CHLORIDE ION × 8 GOL GLYCEROL × 9 B39 [(1S,2S,4R)-4-{4-[(1S)-2,3-dihydro-1H-inden-1-ylamino]-7H-pyrrolo[2,3-d]pyrimidin-7-yl}-2-hydroxycyclopentyl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6；293 K；0.2M lithium sulfate, 0.1M bis-tris, 15% peg 3350
Resolution 2.76 Å R-free 0.220
5L6I Uba1 in complex with Ub-MLN4924 covalent adduct Deposited 2016-05-30 Assembly 2 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain C 1–1024（1024 aa）
Non-standard monomer：Yes (specific site not provided by mmCIF) SO4 SULFATE ION × 1 CL CHLORIDE ION × 8 GOL GLYCEROL × 7 B39 [(1S,2S,4R)-4-{4-[(1S)-2,3-dihydro-1H-inden-1-ylamino]-7H-pyrrolo[2,3-d]pyrimidin-7-yl}-2-hydroxycyclopentyl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6；293 K；0.2M lithium sulfate, 0.1M bis-tris, 15% peg 3350
Resolution 2.76 Å R-free 0.220
5L6J Uba1 in complex with Ub-MLN7243 covalent adduct Deposited 2016-05-30 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 1–1024（1024 aa）
Not recorded SO4 SULFATE ION × 2 CL CHLORIDE ION × 2 GOL GLYCEROL × 7 61T [(1~{R},2~{R},3~{S},4~{R})-2,3-bis(oxidanyl)-4-[[2-[3-(trifluoromethylsulfanyl)phenyl]pyrazolo[1,5-a]pyrimidin-7-yl]amino]cyclopentyl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6；293 K；0.2M lithium sulfate, 0.1M bis-tris, 15% peg 3350
Resolution 2.68 Å R-free 0.224
5L6J Uba1 in complex with Ub-MLN7243 covalent adduct Deposited 2016-05-30 Assembly 2 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain C 1–1024（1024 aa）
Not recorded SO4 SULFATE ION × 1 CL CHLORIDE ION × 2 GOL GLYCEROL × 9 61T [(1~{R},2~{R},3~{S},4~{R})-2,3-bis(oxidanyl)-4-[[2-[3-(trifluoromethylsulfanyl)phenyl]pyrazolo[1,5-a]pyrimidin-7-yl]amino]cyclopentyl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6；293 K；0.2M lithium sulfate, 0.1M bis-tris, 15% peg 3350
Resolution 2.68 Å R-free 0.224
5TR4 Structure of Ubiquitin activating enzyme (Uba1) in complex with ubiquitin and TAK-243 Deposited 2016-10-25 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 9–1024（1016 aa） Fragment：residues 9-1024
Mutation：N471M, K519R 61T [(1~{R},2~{R},3~{S},4~{R})-2,3-bis(oxidanyl)-4-[[2-[3-(trifluoromethylsulfanyl)phenyl]pyrazolo[1,5-a]pyrimidin-7-yl]amino]cyclopentyl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 6；298 K；70 mM Na malonate pH 6.0, 70 mM malic acid, 70 mM Na citrate, 10-15% peg-3350
Resolution 2.20 Å R-free 0.256
5TR4 Structure of Ubiquitin activating enzyme (Uba1) in complex with ubiquitin and TAK-243 Deposited 2016-10-25 Assembly 2 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain C 9–1024（1016 aa） Fragment：residues 9-1024
Mutation：N471M, K519R 61T [(1~{R},2~{R},3~{S},4~{R})-2,3-bis(oxidanyl)-4-[[2-[3-(trifluoromethylsulfanyl)phenyl]pyrazolo[1,5-a]pyrimidin-7-yl]amino]cyclopentyl]methyl sulfamate × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 6；298 K；70 mM Na malonate pH 6.0, 70 mM malic acid, 70 mM Na citrate, 10-15% peg-3350
Resolution 2.20 Å R-free 0.256
6NYA Crystal Structure of ubiquitin E1 (Uba1) in complex with Ubc3 (Cdc34) and ubiquitin Deposited 2019-02-11 Assembly 1 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain A 11–1024（1014 aa） Fragment：residues 11-1024
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 MG MAGNESIUM ION × 1 SO4 SULFATE ION × 8 EDO 1,2-ETHANEDIOL × 12 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 6.5；291 K；0.2 M ammonium sulfate, 25% PEG 3,350, 0.1 M Bis-Tris pH 6.5
Resolution 2.06 Å R-free 0.217
6NYA Crystal Structure of ubiquitin E1 (Uba1) in complex with Ubc3 (Cdc34) and ubiquitin Deposited 2019-02-11 Assembly 2 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain D 11–1024（1014 aa） Fragment：residues 11-1024
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 MG MAGNESIUM ION × 1 SO4 SULFATE ION × 7 EDO 1,2-ETHANEDIOL × 9 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, HANGING DROP；pH 6.5；291 K；0.2 M ammonium sulfate, 25% PEG 3,350, 0.1 M Bis-Tris pH 6.5
Resolution 2.06 Å R-free 0.217
6ZHS Uba1 bound to two E2 (Ubc13) molecules Deposited 2020-06-23 Assembly 1 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain A 1–1024（1024 aa）
Not recorded SO4 SULFATE ION × 2 GOL GLYCEROL × 6 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；273 K；ammonium sulfate, HEPES, PEG 3350
Resolution 2.35 Å R-free 0.275
6ZHT Uba1-Ubc13 disulfide mediated complex Deposited 2020-06-23 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain C 25–1024（1000 aa）
Not recorded GOL GLYCEROL × 12 CL CHLORIDE ION × 4 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；273 K；ammonium nitrate, CHES, PEG 4000
Resolution 2.30 Å R-free 0.263
6ZHU Yeast Uba1 in complex with Ubc3 and ATP Deposited 2020-06-23 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 1–1024（1024 aa）
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 MG MAGNESIUM ION × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；ammonium chloride, PEG 3350
Resolution 3.18 Å R-free 0.263
6ZHU Yeast Uba1 in complex with Ubc3 and ATP Deposited 2020-06-23 Assembly 2 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain E 1–1024（1024 aa）
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 MG MAGNESIUM ION × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；ammonium chloride, PEG 3350
Resolution 3.18 Å R-free 0.263
6ZHU Yeast Uba1 in complex with Ubc3 and ATP Deposited 2020-06-23 Assembly 3 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain C 1–1024（1024 aa）
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 MG MAGNESIUM ION × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；ammonium chloride, PEG 3350
Resolution 3.18 Å R-free 0.263
6ZHU Yeast Uba1 in complex with Ubc3 and ATP Deposited 2020-06-23 Assembly 4 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain G 1–1024（1024 aa）
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 MG MAGNESIUM ION × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；ammonium chloride, PEG 3350
Resolution 3.18 Å R-free 0.263
6ZQH Yeast Uba1 in complex with ubiquitin Deposited 2020-07-09 Assembly 1 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain A 1–1024（1024 aa）
Not recorded BME BETA-MERCAPTOETHANOL × 2 GOL GLYCEROL × 3 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；ammonium formate, PEG 3350
Resolution 2.03 Å R-free 0.227
6ZQH Yeast Uba1 in complex with ubiquitin Deposited 2020-07-09 Assembly 2 Protein heterocomplex Heteromer；Protein × 2 PDB declaration: dimeric（2） Consistent with protein count
Chain C 1–1024（1024 aa）
Not recorded BME BETA-MERCAPTOETHANOL × 2 GOL GLYCEROL × 1 PG4 TETRAETHYLENE GLYCOL × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；293 K；ammonium formate, PEG 3350
Resolution 2.03 Å R-free 0.227
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 1 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain I 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 2 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain C 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 3 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain G 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 4 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain K 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 5 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain S 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 6 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain U 11–1024（1014 aa）
Not recorded No recorded non-water small molecule X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 7 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain D 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7K5J Structure of an E1-E2-ubiquitin thioester mimetic Deposited 2020-09-16 Assembly 8 Protein heterocomplex Heteromer；Protein × 3 PDB declaration: trimeric（3） Consistent with protein count
Chain A 11–1024（1014 aa）
Not recorded AMP ADENOSINE MONOPHOSPHATE × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；pH 6.91；291 K；0.2 M NH4Ac, pH 6.91, 20% PEG3350, 0.02% (+/-)-2-Methyl-2,4-pentanediol, 0.02% 1,2,3,-Heptanetriol, 0.02% Diethylenetriaminepentakis (methylphosphonic acid), 0.02% D-Sorbitol, 0.02% Glycerol, 0.002 M HEPES sodium pH 6.8
Resolution 3.42 Å R-free 0.246
7ZH9 Uba1 in complex with ATP Deposited 2022-04-05 Assembly 1 Protein monomer Monomer；Protein × 1 PDB declaration: monomeric（1） Consistent with protein count
Chain A 1–1024（1024 aa）
Not recorded ATP ADENOSINE-5'-TRIPHOSPHATE × 1 SO4 SULFATE ION × 1 ACT ACETATE ION × 1 MG MAGNESIUM ION × 3 GOL GLYCEROL × 10 K POTASSIUM ION × 1 CL CHLORIDE ION × 1 X-RAY DIFFRACTION
X-ray crystallization conditions VAPOR DIFFUSION, SITTING DROP；289.15 K；0.2 M ammonium sulfate, 0.1 M HEPES pH 7.5 and 25% PEG 3350
Resolution 1.72 Å R-free 0.206

This page presents structural evidence recorded in PDB/mmCIF.“No recorded non-water small molecule” does not prove that the experimental sample was ligand-free; experimental conditions belong to the PDB experiment, while ligands and copy counts are shown for each biological assembly.