3OSQ

Maltose-bound maltose sensor engineered by insertion of circularly permuted green fluorescent protein into E. coli maltose binding protein at position 175


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.165 
  • R-Value Observed: 0.167 

wwPDB Validation   3D Report Full Report


This is version 2.2 of the entry. See complete history


Literature

A genetically encoded, high-signal-to-noise maltose sensor.

Marvin, J.S.Schreiter, E.R.Echevarria, I.M.Looger, L.L.

(2011) Proteins 79: 3025-3036

  • DOI: https://doi.org/10.1002/prot.23118
  • Primary Citation of Related Structures:  
    3OSQ, 3OSR

  • PubMed Abstract: 

    We describe the generation of a family of high-signal-to-noise single-wavelength genetically encoded indicators for maltose. This was achieved by insertion of circularly permuted fluorescent proteins into a bacterial periplasmic binding protein (PBP), Escherichia coli maltodextrin-binding protein, resulting in a four-color family of maltose indicators. The sensors were iteratively optimized to have sufficient brightness and maltose-dependent fluorescence increases for imaging, under both one- and two-photon illumination. We demonstrate that maltose affinity of the sensors can be tuned in a fashion largely independent of the fluorescent readout mechanism. Using literature mutations, the binding specificity could be altered to moderate sucrose preference, but with a significant loss of affinity. We use the soluble sensors in individual E. coli bacteria to observe rapid maltose transport across the plasma membrane, and membrane fusion versions of the sensors on mammalian cells to visualize the addition of maltose to extracellular media. The PBP superfamily includes scaffolds specific for a number of analytes whose visualization would be critical to the reverse engineering of complex systems such as neural networks, biosynthetic pathways, and signal transduction cascades. We expect the methodology outlined here to be useful in the development of indicators for many such analytes.


  • Organizational Affiliation

    Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147, USA. marvinj@janelia.hhmi.org


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Maltose-binding periplasmic protein,Green fluorescent protein661Escherichia coli O157:H7Aequorea victoriaMutation(s): 1 
Gene Names: malEZ5632ECs5017GFP
UniProt
Find proteins for P42212 (Aequorea victoria)
Explore P42212 
Go to UniProtKB:  P42212
Find proteins for P0AEY0 (Escherichia coli O157:H7)
Explore P0AEY0 
Go to UniProtKB:  P0AEY0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupsP42212P0AEY0
Sequence Annotations
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  • Reference Sequence
Oligosaccharides

Help

Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose
B
2N/A
Glycosylation Resources
GlyTouCan:  G07411ON
GlyCosmos:  G07411ON
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
C12
Query on C12
A
L-PEPTIDE LINKINGC15 H18 N3 O4THR, TYR, GLY
Biologically Interesting Molecules (External Reference) 1 Unique
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.165 
  • R-Value Observed: 0.167 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 81.262α = 90
b = 88.686β = 90
c = 119.36γ = 90
Software Package:
Software NamePurpose
specdata collection
PHASERphasing
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2011-10-26
    Type: Initial release
  • Version 1.1: 2013-05-08
    Changes: Database references
  • Version 1.2: 2017-06-21
    Changes: Advisory, Database references, Source and taxonomy, Structure summary
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Non-polymer description, Structure summary
  • Version 2.1: 2023-09-06
    Changes: Data collection, Database references, Refinement description, Structure summary
  • Version 2.2: 2023-12-06
    Changes: Data collection, Derived calculations