6V9Z

Cryo-EM structure of PCAT1 bound to its CtA peptide substrate


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.35 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

Structural basis of substrate recognition by a polypeptide processing and secretion transporter.

Kieuvongngam, V.Olinares, P.D.B.Palillo, A.Oldham, M.L.Chait, B.T.Chen, J.

(2020) Elife 9: --

  • DOI: 10.7554/eLife.51492

  • PubMed Abstract: 
  • The peptidase-containing ATP-binding cassette transporters (PCATs) are unique members of the ABC transporter family that proteolytically process and export peptides and proteins. Each PCAT contains two peptidase domains that cleave off the secretion ...

    The peptidase-containing ATP-binding cassette transporters (PCATs) are unique members of the ABC transporter family that proteolytically process and export peptides and proteins. Each PCAT contains two peptidase domains that cleave off the secretion signal, two transmembrane domains forming a translocation pathway, and two nucleotide-binding domains that hydrolyze ATP. Previously the crystal structures of a PCAT from Clostridium thermocellum (PCAT1) were determined in the absence and presence of ATP, revealing how ATP binding regulates the protease activity and access to the translocation pathway. However, how the substrate CtA, a 90-residue polypeptide, is recognized by PCAT1 remained elusive. To address this question, we determined the structure of the PCAT1-CtA complex by electron cryo-microscopy (cryo-EM) to 3.4 Å resolution. The structure shows that two CtAs are bound via their N-terminal leader peptides, but only one is positioned for cleavage and translocation. Based on these results, we propose a model of how substrate cleavage, ATP hydrolysis, and substrate translocation are coordinated in a transport cycle.


    Organizational Affiliation

    Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States.,Howard Hughes Medical Institute, Chevy Chase, United States.,Laboratory of Membrane Biophysics and Biology, The Rockefeller University, New York, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ABC-type bacteriocin transporter
A, B
730Hungateiclostridium thermocellum (strain ATCC 27405 / DSM 1237 / JCM 9322 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)Mutation(s): 1 
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
Peptidase-containing ABC transporter (PCAT1) bound to CtA peptide substrate
Find proteins for A3DCU1 (Hungateiclostridium thermocellum (strain ATCC 27405 / DSM 1237 / JCM 9322 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372))
Go to UniProtKB:  A3DCU1
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
CtA
C, D
93Hungateiclostridium thermocellum (strain ATCC 27405 / DSM 1237 / JCM 9322 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)Mutation(s): 0 
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
Peptidase-containing ABC transporter (PCAT1) bound to CtA peptide substrate
Find proteins for A3DCU2 (Hungateiclostridium thermocellum (strain ATCC 27405 / DSM 1237 / JCM 9322 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372))
Go to UniProtKB:  A3DCU2
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.35 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
Howard Hughes Medical Institute (HHMI)United States--

Revision History 

  • Version 1.0: 2020-01-22
    Type: Initial release
  • Version 1.1: 2020-01-29
    Type: Database references