4EKV

Streptavidin 8-aa-loop H127C mutein with reversible biotin binding


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.188 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Development of a tetrameric streptavidin mutein with reversible biotin binding capability: engineering a mobile loop as an exit door for biotin.

O'Sullivan, V.J.Barrette-Ng, I.Hommema, E.Hermanson, G.T.Schofield, M.Wu, S.C.Honetschlaeger, C.Ng, K.K.Wong, S.L.

(2012) Plos One 7: e35203-e35203

  • DOI: 10.1371/journal.pone.0035203

  • PubMed Abstract: 
  • A novel form of tetrameric streptavidin has been engineered to have reversible biotin binding capability. In wild-type streptavidin, loop(3-4) functions as a lid for the entry and exit of biotin. When biotin is bound, interactions between biotin and ...

    A novel form of tetrameric streptavidin has been engineered to have reversible biotin binding capability. In wild-type streptavidin, loop(3-4) functions as a lid for the entry and exit of biotin. When biotin is bound, interactions between biotin and key residues in loop(3-4) keep this lid in the closed state. In the engineered mutein, a second biotin exit door is created by changing the amino acid sequence of loop(7-8). This door is mobile even in the presence of the bound biotin and can facilitate the release of biotin from the mutein. Since loop(7-8) is involved in subunit interactions, alteration of this loop in the engineered mutein results in an 11° rotation between the two dimers in reference to wild-type streptavidin. The tetrameric state of the engineered mutein is stabilized by a H127C mutation, which leads to the formation of inter-subunit disulfide bonds. The biotin binding kinetic parameters (k(off) of 4.28×10(-4) s(-1) and K(d) of 1.9×10(-8) M) make this engineered mutein a superb affinity agent for the purification of biotinylated biomolecules. Affinity matrices can be regenerated using gentle procedures, and regenerated matrices can be reused at least ten times without any observable reduction in binding capacity. With the combination of both the engineered mutein and wild-type streptavidin, biotinylated biomolecules can easily be affinity purified to high purity and immobilized to desirable platforms without any leakage concerns. Other potential biotechnological applications, such as development of an automated high-throughput protein purification system, are feasible.


    Organizational Affiliation

    Thermo Fisher Scientific, Inc., Pierce Protein Research, Rockford, Illinois, United States of America.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Streptavidin
A
159Streptomyces avidiniiMutation(s): 1 
Find proteins for P22629 (Streptomyces avidinii)
Go to UniProtKB:  P22629
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
BTN
Query on BTN

Download SDF File 
Download CCD File 
A
BIOTIN
C10 H16 N2 O3 S
YBJHBAHKTGYVGT-ZKWXMUAHSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
BTNKd: 1 nM (94) BINDINGDB
BTNΔH: -66.9 - -123 kJ/mol (94) BINDINGDB
BTNKd: 1450 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.188 
  • Space Group: P 42 21 2
Unit Cell:
Length (Å)Angle (°)
a = 57.066α = 90.00
b = 57.066β = 90.00
c = 70.186γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
SCALEPACKdata scaling
REFMACrefinement
DENZOdata reduction
PHASERphasing
MAR345data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-06-13
    Type: Initial release
  • Version 1.1: 2017-11-15
    Type: Refinement description