Biological Assembly 1  

 3D View: Structure | Electron Density

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 16.09 kDa 
• Atom Count: 1228 
• Modelled Residue Count: 148 
• Deposited Residue Count: 151 
• Unique protein chains: 1

1RJ1

Crystal Structure of a Cell Wall Invertase Inhibitor from Tobacco

• DOI: 10.2210/pdb1RJ1/pdb

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


• Deposited: 2003-11-18 Released: 2004-02-03 
• Deposition Author(s): Hothorn, M., D'Angelo, I., Marquez, J.A., Greiner, S., Scheffzek, K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.87 Å
• R-Value Free: 0.232 
• R-Value Work: 0.194 
• R-Value Observed: 0.194 

Literature

The invertase inhibitor Nt-CIF from tobacco: a highly thermostable four-helix bundle with an unusual N-terminal extension

Hothorn, M., D'Angelo, I., Marquez, J.A., Greiner, S., Scheffzek, K.

(2004) J Mol Biol 335: 987-995

• PubMed: 14698293 
• DOI: 10.1016/j.jmb.2003.10.066
• Primary Citation of Related Structures:  
  1RJ4, 1RJ1


• PubMed Abstract: 
  

Plant invertases are sucrolytic enzymes essential for plant metabolism and development. Enzyme activity is regulated on a posttranslational level via inhibitory proteins, referred to as invertase inhibitors. Ectopic expression of invertase inhibitors in crop plants has high biotechnological potential. However, little biochemical and up to now no detailed structural information is available about this class of plant regulatory proteins. Here, we present the crystal structure of the cell wall-associated invertase inhibitor Nt-CIF from tobacco at a resolution of 1.87A. The structural model reveals an asymmetric four-helix bundle with an uncommon N-terminal extension that appears to be critical for the structural integrity of the protein. Structure analysis of a second crystal form grown in the presence of CdCl(2) reveals two metal binding sites. Nt-CIF is highly thermostable and retains full inhibitory activity after cooling to ambient temperatures. The structure of Nt-CIF provides the first three-dimensional information source for the posttranslational regulation of plant invertases. Based on the recently discovered sequence homology between inhibitors of invertases and pectin methylesterases, our structural model is likely to represent a scaffold also used for the regulation of the latter enzymes, which do not share sequence similarity with invertases. Thus, our structural model sets the 3D-stage for the investigation of posttranslational regulation of invertases as well as pectin methylesterases.

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Organizational Affiliation: 

European Molecular Biology Laboratory, Structural and Computational Biology Programme, Meyerhofstr. 1, 69117 Heidelberg, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
invertase inhibitor	A	151	Nicotiana tabacum	Mutation(s): 0  Gene Names: NTINH1, LOC107808322
UniProt
Find proteins for O49908 (Nicotiana tabacum) Explore O49908  Go to UniProtKB:  O49908

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.87 Å
• R-Value Free: 0.232 
• R-Value Work: 0.194 
• R-Value Observed: 0.194 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 60.67	α = 90
b = 106.4	β = 90
c = 55.81	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
XDS	data reduction
XDS	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-11-18 
• Released Date: 2004-02-03 
Deposition Author(s): Hothorn, M., D'Angelo, I., Marquez, J.A., Greiner, S., Scheffzek, K.

Revision History  

• Version 1.0: 2004-02-03
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance