1XQG

3.10 A crystal structure of maspin, Space group P 4 21 2

• PDB DOI: https://doi.org/10.2210/pdb1XQG/pdb

• Classification: ANTITUMOR PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2004-10-12 Released: 2004-10-26 
• Deposition Author(s): Al-Ayyoubi, M., Gettins, P.G., Volz, K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.10 Å
• R-Value Free: 0.252 
• R-Value Work: 0.194 
• R-Value Observed: 0.194 

Starting Models: experimental

Literature

Crystal Structure of Human Maspin, a Serpin with Antitumor Properties: Reactive Center Loop of Mapsin is Exposed but Constrained

Al-Ayyoubi, M., Gettins, P.G., Volz, K.

(2004) J Biol Chem 279: 55540-55544

• PubMed: 15501821 
• DOI: https://doi.org/10.1074/jbc.M409957200
• Primary Citation of Related Structures:  
  1XQG, 1XQJ


• PubMed Abstract: 
  

  Maspin, a member of the serpin superfamily, has tumor suppressing activity against breast and prostate cancer. Maspin inhibits tumor growth by blocking cell invasion, and its reactive center loop (RCL) is thought to mediate this activity. To understand this function on the molecular level, we have solved the three-dimensional structure of Maspin to 3.1 A resolution. The molecular structure shows the characteristic features of the serpin fold, but the RCL of Maspin is unique in length, composition, and placement. Although the RCL of Maspin is accessible and cleavable by some proteinases, it functions in the uncleaved, constrained conformation observed here. These structural results will contribute to our understanding of the mechanism by which Maspin suppresses tumors.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, University of Illinois at Chicago, 835 S. Wolcott Avenue, Chicago, IL 60612-7334.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly 2  

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

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 87.55 kDa 
• Atom Count: 6,074 
• Modelled Residue Count: 756 
• Deposited Residue Count: 778 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Maspin	A, B	389	Homo sapiens	Mutation(s): 8  Gene Names: SERPINB5, PI5
UniProt & NIH Common Fund Data Resources
Find proteins for P36952 (Homo sapiens) Explore P36952  Go to UniProtKB:  P36952
PHAROS:  P36952 GTEx:  ENSG00000206075

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.10 Å
• R-Value Free: 0.252 
• R-Value Work: 0.194 
• R-Value Observed: 0.194 
• Space Group: P 4 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 147.462	α = 90
b = 147.462	β = 90
c = 118.038	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data collection
HKL-2000	data reduction
CNS	refinement
HKL-2000	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2004-10-26 
Deposition Author(s): Al-Ayyoubi, M., Gettins, P.G., Volz, K.

Revision History  

• Version 1.0: 2004-10-26
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2021-10-20
  Changes: Database references
• Version 1.4: 2023-08-23
  Changes: Data collection, Refinement description