5J9P

KcsA in vitro


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.217 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Combining in Vitro Folding with Cell Free Protein Synthesis for Membrane Protein Expression.

Focke, P.J.Hein, C.Hoffmann, B.Matulef, K.Bernhard, F.Dotsch, V.Valiyaveetil, F.I.

(2016) Biochemistry 55: 4212-4219

  • DOI: 10.1021/acs.biochem.6b00488

  • PubMed Abstract: 
  • Cell free protein synthesis (CFPS) has emerged as a promising methodology for protein expression. While polypeptide production is very reliable and efficient using CFPS, the correct cotranslational folding of membrane proteins during CFPS is still a ...

    Cell free protein synthesis (CFPS) has emerged as a promising methodology for protein expression. While polypeptide production is very reliable and efficient using CFPS, the correct cotranslational folding of membrane proteins during CFPS is still a challenge. In this contribution, we describe a two-step protocol in which the integral membrane protein is initially expressed by CFPS as a precipitate followed by an in vitro folding procedure using lipid vesicles for converting the protein precipitate to the correctly folded protein. We demonstrate the feasibility of using this approach for the K(+) channels KcsA and MVP and the amino acid transporter LeuT. We determine the crystal structure of the KcsA channel obtained by CFPS and in vitro folding to show the structural similarity to the cellular expressed KcsA channel and to establish the feasibility of using this two-step approach for membrane protein production for structural studies. Our studies show that the correct folding of these membrane proteins with complex topologies can take place in vitro without the involvement of the cellular machinery for membrane protein biogenesis. This indicates that the folding instructions for these complex membrane proteins are contained entirely within the protein sequence.


    Organizational Affiliation

    Program in Chemical Biology, Department of Physiology and Pharmacology, Oregon Health & Science University , 3181 Southwest Sam Jackson Park Road, Portland, Oregon 97239, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fab
A
219N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Fab
B
212N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
pH-gated potassium channel KcsA
C
96Streptomyces lividansMutation(s): 0 
Gene Names: kcsA (skc1)
Find proteins for P0A334 (Streptomyces lividans)
Go to UniProtKB:  P0A334
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
C
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.217 
  • Space Group: I 4
Unit Cell:
Length (Å)Angle (°)
a = 155.695α = 90.00
b = 155.695β = 90.00
c = 74.791γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
PHENIXrefinement
SCALAdata scaling
PDB_EXTRACTdata extraction
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of HealthUnited States--

Revision History 

  • Version 1.0: 2016-07-20
    Type: Initial release
  • Version 1.1: 2016-08-10
    Type: Database references
  • Version 1.2: 2017-09-27
    Type: Author supporting evidence, Database references, Derived calculations