4HRS

Crystal structure of H. volcanii small archaeal modifier protein 2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.215 
  • R-Value Observed: 0.217 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of the ubiquitin-like small archaeal modifier protein 2 from Haloferax volcanii.

Li, Y.Maciejewski, M.W.Martin, J.Jin, K.Zhang, Y.Maupin-Furlow, J.A.Hao, B.

(2013) Protein Sci 22: 1206-1217

  • DOI: 10.1002/pro.2305
  • Primary Citation of Related Structures:  
    2M19, 4HRS

  • PubMed Abstract: 
  • The discovery of ubiquitin-like small archaeal modifier protein 2 (SAMP2) that forms covalent polymeric chains in Haloferax volcanii has generated tremendous interest in the function and regulation of this protein. At present, it remains unclear whether the Hfx ...

    The discovery of ubiquitin-like small archaeal modifier protein 2 (SAMP2) that forms covalent polymeric chains in Haloferax volcanii has generated tremendous interest in the function and regulation of this protein. At present, it remains unclear whether the Hfx. volcanii modifier protein SAMP1 has such polyubiquitinating-like activity. Although SAMP1 and SAMP2 use the same conjugation machinery to modify their target proteins, each can impart distinct functional consequences. To better understand the mechanism of SAMP2 conjugation, we have sought to characterize the biophysical and structural properties of the protein from Hfx. volcanii. SAMP2 is only partially structured under mesohalic solution conditions and adopts a well-folded compact conformation in the presence of 2.5M of NaCl. Its 2.3-Å-resolution crystal structure reveals a characteristic α/β central core domain and a unique β-hinge motif. This motif anchors an unusual C-terminal extension comprising the diglycine tail as well as two lysine residues that can potentially serve to interlink SAMP2 moieties. Mutational alternation of the structural malleability of this β-hinge motif essentially abolishes the conjugation activity of SAMP2 in vivo. In addition, NMR structural studies of the putative ubiquitin-like protein HVO_2177 from Hfx. volcanii show that like SAMP1, HVO_2177 forms a classic β-grasp fold in a salt-independent manner. These results provide insights into the structure-function relationship of sampylating proteins of fundamental importance in post-translational protein modification and environmental cues in Archaea.


    Organizational Affiliation

    Department of Molecular, Microbial, and Structural Biology, University of Connecticut Health Center, Farmington, Connecticut, 06030.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Small archaeal modifier protein 2A67Haloferax volcanii DS2Mutation(s): 0 
Gene Names: HVO_0202samp2
UniProt
Find proteins for D4GZE7 (Haloferax volcanii (strain ATCC 29605 / DSM 3757 / JCM 8879 / NBRC 14742 / NCIMB 2012 / VKM B-1768 / DS2))
Explore D4GZE7 
Go to UniProtKB:  D4GZE7
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.30 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.215 
  • R-Value Observed: 0.217 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 24.605α = 90
b = 64.603β = 90
c = 104.555γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
PHASERphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

  • Deposited Date: 2012-10-28 
  • Released Date: 2013-08-07 
  • Deposition Author(s): Hao, B.

Revision History  (Full details and data files)

  • Version 1.0: 2013-08-07
    Type: Initial release
  • Version 1.1: 2013-08-21
    Changes: Database references
  • Version 1.2: 2013-10-02
    Changes: Database references