7MQ7

Tetragonal Maltose Binding Protein

• PDB DOI: https://doi.org/10.2210/pdb7MQ7/pdb

• Classification: SUGAR BINDING PROTEIN
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2021-05-05 Released: 2021-09-08 
• Deposition Author(s): Thaker, A., Sirajudeen, L., Simmons, C.R., Nannenga, B.L.
• Funding Organization(s): Department of Defense (DOD, United States)

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.95 Å
• R-Value Free: 0.235 
• R-Value Work: 0.195 
• R-Value Observed: 0.197 

Literature

Structure-guided identification of a peptide for bio-enabled gold nanoparticle synthesis.

Thaker, A., Sirajudeen, L., Simmons, C.R., Nannenga, B.L.

(2021) Biotechnol Bioeng 118: 4867-4873

• PubMed: 34436761 
• DOI: https://doi.org/10.1002/bit.27927
• Primary Citation of Related Structures:  
  7MQ6, 7MQ7


• PubMed Abstract: 
  

  In this study, we show that maltose-binding protein (MBP) is capable of facilitating stable gold nanoparticle synthesis, and a structure of MBP in the presence of gold ions was determined by X-ray crystallography. Using this high-resolution structure of gold ion bound MBP, a peptide (AT1) was selected and synthesized and was shown to also aid in the synthesis of stable gold nanoparticles under similar experimental conditions to those used for protein facilitated synthesis. This structure-based approach represents a new potential method for the selection of peptides capable of facilitating stable nanoparticle synthesis.

---

Organizational Affiliation: 

Chemical Engineering, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, Arizona, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 41.79 kDa 
• Atom Count: 3,302 
• Modelled Residue Count: 373 
• Deposited Residue Count: 373 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Maltodextrin-binding protein	A	373	Escherichia coli	Mutation(s): 0  Gene Names: malE, GF950_09430
UniProt
Find proteins for P0AEX9 (Escherichia coli (strain K12)) Explore P0AEX9  Go to UniProtKB:  P0AEX9

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Length	2D Diagram	Glycosylation	3D Interactions
alpha-D-glucopyranose-(1-4)-beta-D-glucopyranose	B	2		N/A
Glycosylation Resources
GlyTouCan:  G66120GK GlyCosmos:  G66120GK

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	C [auth A], D [auth A], E [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L
CL	F [auth A], G [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Biologically Interesting Molecules (External Reference) 1 Unique

Entity ID: 2
ID	Chains	Name	Type/Class	2D Diagram	3D Interactions
PRD_900018	B	beta-maltose	Oligosaccharide / Nutrient

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.95 Å
• R-Value Free: 0.235 
• R-Value Work: 0.195 
• R-Value Observed: 0.197 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 69.07	α = 90
b = 69.07	β = 90
c = 211.803	γ = 90

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
PHENIX	refinement
PDB_EXTRACT	data extraction
HKL-2000	data reduction
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2021-09-08 
Deposition Author(s): Thaker, A., Sirajudeen, L., Simmons, C.R., Nannenga, B.L.

---

Funding Organization	Location	Grant Number
Department of Defense (DOD, United States)	United States	--

Revision History  

• Version 1.0: 2021-09-08
  Type: Initial release
  
• Version 1.1: 2021-11-24
  Changes: Database references
• Version 1.2: 2023-10-18
  Changes: Data collection, Refinement description