22ES: Gi bound kappa-opioid receptor

Gi bound kappa-opioid receptor in complex with difelikefalin. Determined by electron microscopy at 2.43 Å resolution. Released 6 May 2026.

Method
Electron microscopy
Resolution
2.43 Å
Organisms
Rattus norvegicus, Bos taurus, Homo sapiens
Chains
6
Atoms
9,028
Mol. weight
162.65 kDa
Ligands
CLR
Released
6 May 2026

Explore 22ES in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

22ES contains 41 α-helices and 64 β-strands across 5 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 B: 4 helices, 28 β-strands

ElementResiduesLengthSheet
α-helix8-2518
α-helix30-345
α-helix38-392
β-strand47-5151
β-strand58-6362
β-strand69-7462
β-strand78-8362
β-strand89-9462
β-strand100-10563
β-strand111-11663
β-strand120-12563
β-strand134-14073
β-strand146-15164
β-strand156-16164
β-strand166-17054
β-strand176-18054
β-strand187-19265
β-strand198-20365
β-strand207-21265
β-strand218-22365
β-strand229-23466
β-strand240-24566
β-strand250-25456
β-strand259-26466
α-helix2721
β-strand273-27867
β-strand284-28967
β-strand294-29857
β-strand304-30857
β-strand315-32061
β-strand327-33151
β-strand336-33941
Chain C: 3 helices, 0 β-strands
ElementResiduesLengthSheet
α-helix10-2314
α-helix30-4314
α-helix53-553
Chain D: 13 helices, 8 β-strands
ElementResiduesLengthSheet
α-helix7-3226
β-strand34-39610
α-helix42-443
α-helix47-548
β-strand185-190610
β-strand195-200610
α-helix212-2154
β-strand220-226710
α-helix227-2304
α-helix2321
β-strand233111
α-helix2341
β-strand241111
α-helix242-25413
α-helix257-2593
β-strand263-269710
α-helix271-2788
α-helix283-2853
α-helix296-30813
β-strand319-323510
α-helix331-35121
Chain E: 6 helices, 24 β-strands
ElementResiduesLengthSheet
β-strand3-7512
β-strand10-12313
β-strand17-25912
α-helix29-313
β-strand33-39713
β-strand45-51713
α-helix53-553
β-strand58-60313
β-strand68-73612
β-strand78-84712
α-helix88-903
β-strand92-99813
β-strand110-111213
β-strand115-119513
α-helix139-1402
β-strand141-143314
β-strand147-149315
β-strand156-162714
β-strand167116
β-strand173116
β-strand175-180615
β-strand187-191515
β-strand195-196215
α-helix1971
β-strand204-208514
β-strand212-217614
α-helix222-2243
β-strand227-232615
β-strand240115
β-strand244-247415
Chain R: 15 helices, 4 β-strands
ElementResiduesLengthSheet
α-helix58-8326
α-helix84-885
α-helix93-12129
α-helix128-16134
α-helix163-1697
α-helix172-19625
β-strand19718
β-strand200-20239
β-strand207-20939
α-helix2111
β-strand21218
α-helix2131
α-helix219-23113
α-helix232-2365
α-helix237-25418
α-helix263-29937
α-helix306-32722
α-helix328-3325
α-helix335-3417

Molecules and chains

MoleculeChainsTypeLengthOrganismUniProt
Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1Bprotein354Rattus norvegicusP54311 (AlphaFold model)
Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2Cprotein71Bos taurusP63212 (AlphaFold model)
Kappa-type opioid receptorRprotein397Homo sapiensP41145 (AlphaFold model)
Guanine nucleotide-binding protein G(i) subunit alpha-1Dprotein354Homo sapiensP63096 (AlphaFold model)
scFv16Eprotein266synthetic construct
Dpn-dpn-dle-dly-A1L9XAprotein5synthetic construct
Sequence of entity 1 (B), FASTA
>22ES_1 Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1 (chains B)
MHHHHHHHHMGSLLQSELDQLRQEAEQLKNQIRDARKACADATLSQITNNIDPVGRIQMR
TRRTLRGHLAKIYAMHWGTDSRLLVSASQDGKLIIWDSYTTNKVHAIPLRSSWVMTCAYA
PSGNYVACGGLDNICSIYNLKTREGNVRVSRELAGHTGYLSCCRFLDDNQIVTSSGDTTC
ALWDIETGQQTTTFTGHTGDVMSLSLAPDTRLFVSGACDASAKLWDVREGMCRQTFTGHE
SDINAICFFPNGNAFATGSDDATCRLFDLRADQELMTYSHDNIICGITSVSFSKSGRLLL
AGYDDFNCNVWDALKADRAGVLAGHDNRVSCLGVTDDGMAVATGSWDSFLKIWN
Sequence of entity 2 (C), FASTA
>22ES_2 Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2 (chains C)
MASNNTASIAQARKLVEQLKMEANIDRIKVSKAAADLMAYCEAHAKEDPLLTPVPASENP
FREKKFFCAIL
Sequence of entity 3 (R), FASTA
>22ES_3 Kappa-type opioid receptor (chains R)
DYKDDDDVDASSPIQIFRGEPGPTCAPSACLPPNSSAWFPGWAEPDSNGSAGSEDAQLEP
AHISPAIPVIITAVYSVVFVVGLVGNSLVMFVIIRYTKMKTATNIYIFNLALADALVTTT
MPFQSTVYLMNSWPFGDVLCKIVISIDYYNMFTSIFTLTMMSVDRYIAVCHPVKALDFRT
PLKAKIINICIWLLSSSVGISAIVLGGTKVREDVDVIECSLQFPDDDYSWWDLFMKICVF
IFAFVIPVLIIIVCYTLMILRLKSVRLLSGSREKDRNLRRITRLVLVVVAVFVVCWTPIH
IFILVEALGSTSHSTAALSSYYFCIALGYTNSSLNPILYAFLDENFKRCFRDFCFPLKMR
MERQSTSRVRNTVQDPAYLRDIDGMNKPVHHHHHHHH
Sequence of entity 4 (D), FASTA
>22ES_4 Guanine nucleotide-binding protein G(i) subunit alpha-1 (chains D)
MGCTLSAEDKAAVERSKMIDRNLREDGEKAAREVKLLLLGAGESGKNTIVKQMKIIHEAG
YSEEECKQYKAVVYSNTIQSIIAIIRAMGRLKIDFGDSARADDARQLFVLAGAAEEGFMT
AELAGVIKRLWKDSGVQACFNRSREYQLNDSAAYYLNDLDRIAQPNYIPTQQDVLRTRVK
TTGIVETHFTFKDLHFKMFDVGAQRSERKKWIHCFEGVTAIIFCVALSDYDLVLAEDEEM
NRMHASMKLFDSICNNKWFTDTSIILFLNKKDLFEEKIKKSPLTICYPEYAGSNTYEEAA
AYIQCQFEDLNKRKDTKEIYTHFTCSTDTKNVQFVFDAVTDVIIKNNLKDCGLF
Sequence of entity 5 (E), FASTA
>22ES_5 scFv16 (chains E)
VQLVESGGGLVQPGGSRKLSCSASGFAFSSFGMHWVRQAPEKGLEWVAYISSGSGTIYYA
DTVKGRFTISRDDPKNTLFLQMTSLRSEDTAMYYCVRSIYYYGSSPFDFWGQGTTLTVSA
GGGGSGGGGSGGGGSADIVMTQATSSVPVTPGESVSISCRSSKSLLHSNGNTYLYWFLQR
PGQSPQLLIYRMSNLASGVPDRFSGSGSGTAFTLTISRLEAEDVGVYYCMQHLEYPLTFG
AGTKLELVDENLYFQGASHHHHHHHH
Sequence of entity 6 (A), FASTA
>22ES_6 DPN-DPN-DLE-DLY-A1L9X (chains A)
FFLKX

Ligands and cofactors

IDNameFormulaCopies
CLRCholesterolC27 H46 O3

Primary citation

Gi bound kappa-opioid receptor in complex with difelikefalin. Zhang, H., Wang, R., Shi, P. et al. To be published.

Other PDB entries of the same protein (UniProt P54311 (AlphaFold model), which also has an AlphaFold model), best resolution first:

Browse structure collections

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