6H03

OPEN CONFORMATION OF THE MEMBRANE ATTACK COMPLEX


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 5.6 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

CryoEM reveals how the complement membrane attack complex ruptures lipid bilayers.

Menny, A.Serna, M.Boyd, C.M.Gardner, S.Joseph, A.P.Morgan, B.P.Topf, M.Brooks, N.J.Bubeck, D.

(2018) Nat Commun 9: 5316-5316

  • DOI: 10.1038/s41467-018-07653-5
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The membrane attack complex (MAC) is one of the immune system's first responders. Complement proteins assemble on target membranes to form pores that lyse pathogens and impact tissue homeostasis of self-cells. How MAC disrupts the membrane barrier re ...

    The membrane attack complex (MAC) is one of the immune system's first responders. Complement proteins assemble on target membranes to form pores that lyse pathogens and impact tissue homeostasis of self-cells. How MAC disrupts the membrane barrier remains unclear. Here we use electron cryo-microscopy and flicker spectroscopy to show that MAC interacts with lipid bilayers in two distinct ways. Whereas C6 and C7 associate with the outer leaflet and reduce the energy for membrane bending, C8 and C9 traverse the bilayer increasing membrane rigidity. CryoEM reconstructions reveal plasticity of the MAC pore and demonstrate how C5b6 acts as a platform, directing assembly of a giant β-barrel whose structure is supported by a glycan scaffold. Our work provides a structural basis for understanding how β-pore forming proteins breach the membrane and reveals a mechanism for how MAC kills pathogens and regulates cell functions.


    Organizational Affiliation

    Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London, SW7 2AZ, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Complement C5,Complement C5
A
1580Homo sapiensMutation(s): 0 
Gene Names: C5 (CPAMD4)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P01031 (Homo sapiens)
Go to Gene View: C5
Go to UniProtKB:  P01031
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Complement component C8 beta chain
C
537Homo sapiensMutation(s): 0 
Gene Names: C8B
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P07358 (Homo sapiens)
Go to Gene View: C8B
Go to UniProtKB:  P07358
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Complement component C7
D
821Homo sapiensMutation(s): 0 
Gene Names: C7
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P10643 (Homo sapiens)
Go to Gene View: C7
Go to UniProtKB:  P10643
Entity ID: 4
MoleculeChainsSequence LengthOrganismDetails
Complement component C8 gamma chain
E
182Homo sapiensMutation(s): 0 
Gene Names: C8G
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P07360 (Homo sapiens)
Go to Gene View: C8G
Go to UniProtKB:  P07360
Entity ID: 5
MoleculeChainsSequence LengthOrganismDetails
Complement component C8 alpha chain
F
554Homo sapiensMutation(s): 0 
Gene Names: C8A
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P07357 (Homo sapiens)
Go to Gene View: C8A
Go to UniProtKB:  P07357
Entity ID: 6
MoleculeChainsSequence LengthOrganismDetails
Complement component C6
B
913Homo sapiensMutation(s): 0 
Gene Names: C6
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P13671 (Homo sapiens)
Go to Gene View: C6
Go to UniProtKB:  P13671
Entity ID: 7
MoleculeChainsSequence LengthOrganismDetails
Complement component C9
G, P, H, I, J, K, L, M, N, O, Q, R, S, T, U, V, W, X
538Homo sapiensMutation(s): 0 
Gene Names: C9
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Adventitious Membrane Proteins: Beta-sheet Pore-forming Toxins/Attack Complexes
Protein: 
poly-C9 component of the complement membrane attack Complex
Find proteins for P02748 (Homo sapiens)
Go to Gene View: C9
Go to UniProtKB:  P02748
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
BMA
Query on BMA

Download SDF File 
Download CCD File 
C
BETA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-RWOPYEJCSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
B, C, D, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 5.6 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Cancer Research UKUnited KingdomC26409/A16099
Medical Research Council (United Kingdom)United KingdomMR/M019292/1

Revision History 

  • Version 1.0: 2018-12-19
    Type: Initial release
  • Version 1.1: 2018-12-26
    Type: Author supporting evidence, Data collection, Database references