9KPZ: TolQRA complex at pH 5.4 from E.coli
Structure of TolQRA complex at pH 5.4 from E.coli. Determined by electron microscopy at 3.18 Å resolution. Released 4 Mar 2026.
- Method
- Electron microscopy
- Resolution
- 3.18 Å
- Organisms
- Escherichia coli K-12, Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
- Chains
- 12
- Atoms
- 10,447
- Mol. weight
- 457.4 kDa
- Ligands
- 3PE
- Released
- 4 Mar 2026
Explore 9KPZ in 3D
Show helices and sheets
RCSB PDB
PDBe
Secondary structure: helices and β-sheets
9KPZ contains 47 α-helices and 0 β-strands across 12 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: 9 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 6-12 | 7 | |
| α-helix | 15-57 | 43 | |
| α-helix | 62-72 | 11 | |
| α-helix | 73-75 | 3 | |
| α-helix | 79-94 | 16 | |
| α-helix | 101-123 | 23 | |
| α-helix | 127-157 | 31 | |
| α-helix | 168-183 | 16 | |
| α-helix | 186-220 | 35 | |
Chain B: 7 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 7-12 | 6 | |
| α-helix | 15-56 | 42 | |
| α-helix | 62-71 | 10 | |
| α-helix | 79-96 | 18 | |
| α-helix | 101-123 | 23 | |
| α-helix | 127-154 | 28 | |
| α-helix | 168-223 | 56 | |
Chain C: 7 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 8-12 | 5 | |
| α-helix | 15-57 | 43 | |
| α-helix | 62-72 | 11 | |
| α-helix | 79-96 | 18 | |
| α-helix | 101-124 | 24 | |
| α-helix | 127-158 | 32 | |
| α-helix | 168-221 | 54 | |
Chain D: 8 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 8-11 | 4 | |
| α-helix | 16-56 | 41 | |
| α-helix | 62-71 | 10 | |
| α-helix | 73-75 | 3 | |
| α-helix | 79-96 | 18 | |
| α-helix | 104-123 | 20 | |
| α-helix | 127-156 | 30 | |
| α-helix | 168-220 | 53 | |
Chain E: 7 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 6-12 | 7 | |
| α-helix | 15-56 | 42 | |
| α-helix | 62-71 | 10 | |
| α-helix | 78-95 | 18 | |
| α-helix | 101-123 | 23 | |
| α-helix | 127-157 | 31 | |
| α-helix | 168-220 | 53 | |
Chain F: 2 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 20-23 | 4 | |
| α-helix | 25-34 | 10 | |
Chain G: 2 helices, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 18-32 | 15 | |
| α-helix | 33-35 | 3 | |
Chain H: 1 helix, 0 β-strands
| Element | Residues | Length | Sheet |
|---|
| α-helix | 9-34 | 26 | |
2 more chain groups are not listed. Open the entry in the viewer and use the sequence panel to see them.
Molecules and chains
| Molecule | Chains | Type | Length | Organism | UniProt |
|---|
| Tol-Pal system protein TolQ | A, B, C, D, E | protein | 232 | Escherichia coli K-12 | P0ABU9 (AlphaFold model) |
| Tol-Pal system protein TolR | F, G | protein | 142 | Escherichia coli K-12 | P0ABV6 (AlphaFold model) |
| Ubiquitin-like protein SMT3,Tol-Pal system protein TolA | H, I, J, K, L | protein | 557 | Saccharomyces cerevisiae (strain ATCC 204508 / S288c), Escherichia coli K-12 | P19934 (AlphaFold model), Q12306 (AlphaFold model) |
Sequence of entity 1 (A, B, C, D, E), FASTA
>9KPZ_1 Tol-Pal system protein TolQ (chains A, B, C, D, E)
MGVTDMNILDLFLKASLLVKLIMLILIGFSIASWAIIIQRTRILNAAAREAEAFEDKFWS
GIELSRLYQESQGKRDNLTGSEQIFYSGFKEFVRLHRANSHAPEAVVEGASRAMRISMNR
ELENLETHIPFLGTVGSISPYIGLFGTVWGIMHAFIALGAVKQATLQMVAPGIAEALIAT
AIGLFAAIPAVMAYNRLNQRVNKLELNYDNFMEEFTAILHRQAFTVSESNKG
Sequence of entity 2 (F, G), FASTA
>9KPZ_2 Tol-Pal system protein TolR (chains F, G)
MARARGRGRRDLKSEINIVPLLDVLLVLLLIFMATAPIITQSVEVDLPDATESQAVSSND
NPPVIVEVSGIGQYTVVVEKDRLERLPPEQVVAEVSSRFKANPKTVFLIGGAKDVPYDEI
IKALNLLHSAGVKSVGLMTQPI
Sequence of entity 3 (H, I, J, K, L), FASTA
>9KPZ_3 Ubiquitin-like protein SMT3,Tol-Pal system protein TolA (chains H, I, J, K, L)
MGHHHHHHHHGSLQDSEVNQEAKPEVKPEVKPETHINLKVSDGSSEIFFKIKKTTPLRRL
MEAFAKRQGKEMDSLRFLYDGIRIQADQTPEDLDMEDNDIIEAHREQIGGAAADYGGDIP
TTENLYFQGAAADIGSVSKATEQNDKLKRAIIISAVLHVILFAALIWSSFDENIEASAGG
GGGSSIDAVMVDSGAVVEQYKRMQSQESSAKRSDEQRKMKEQQAAEELREKQAAEQERLK
QLEKERLAAQEQKKQAEEAAKQAELKQKQAEEAAAKAAADAKAKAEADAKAAEEAAKKAA
ADAKKKAEAEAAKAAAEAQKKAEAAAAALKKKAEAAEAAAAEARKKAATEAAEKAKAEAE
KKAAAEKAAADKKAAAEKAAADKKAAEKAAAEKAAADKKAAAEKAAADKKAAAAKAAAEK
AAAAKAAAEADDIFGELSSGKNAPKTGGGAKGNNASPAGSGNTKNNGASGADINNYAGQI
KSAIESKFYDASSYAGKTCTLRIKLAPDGMLLDIKPEGGDPALCQAALAAAKLAKIPKPP
SQAVYEVFKNAPLDFKP
Ligands and cofactors
| ID | Name | Formula | Copies |
|---|
| 3PE | 1,2-Distearoyl-sn-glycerophosphoethanolamine | C41 H82 N O8 P | 7 |
Primary citation
Structure of TolQRA complex at pH 5.4 from E.coli. Dong, C., Zhang, Z. To be published.
Other PDB entries of the same protein (UniProt P0ABU9 (AlphaFold model), which also has an AlphaFold model), best resolution first:
- 9O40 2.92 Å, cryo-EM structure of TolQR conformation1 in SMA nanodiscs
- 9DDM 2.94 Å, E. coli TolAQR conformation I
- 9DDN 3.18 Å, E. coli TolAQR conformation II
- 9QUQ 3.28 Å, cryo-EM structure of TolQR conformation2 in SMA nanodiscs
- 9QVD 3.52 Å, cryo-EM structure of TolQRA in nanodiscs
- 9K49 3.6 Å, Cryo-EM structure of inner membrane TolQRA complex in CYMAL-6-Neopentyl Glycol detergent…
- 9KQ0 3.6 Å, Structure of TolQRA complex at pH 8.0 from E.coli
- 9KCH 4.19 Å, Cryo-EM structure of inner membrane TolQRA complex in CYMAL-6-Neopentyl Glycol detergent…
- 8ODT 4.2 Å, Structure of TolQR complex from E.coli
Browse structure collections
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