2RBH

Gamma-glutamyl cyclotransferase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The identification and structural characterization of C7orf24 as gamma-glutamyl cyclotransferase. An essential enzyme in the gamma-glutamyl cycle

Oakley, A.J.Yamada, T.Liu, D.Coggan, M.Clark, A.G.Board, P.G.

(2008) J.Biol.Chem. 283: 22031-22042

  • DOI: 10.1074/jbc.M803623200
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The hypothetical protein C7orf24 has been implicated as a cancer marker with a potential role in cell proliferation. We have identified C7orf24 as gamma-glutamyl cyclotransferase (GGCT) that catalyzes the formation of 5-oxoproline (pyroglutamic acid) ...

    The hypothetical protein C7orf24 has been implicated as a cancer marker with a potential role in cell proliferation. We have identified C7orf24 as gamma-glutamyl cyclotransferase (GGCT) that catalyzes the formation of 5-oxoproline (pyroglutamic acid) from gamma-glutamyl dipeptides and potentially plays a significant role in glutathione homeostasis. In the present study we have identified the first cDNA clones encoding a gamma-glutamyl cyclotransferase. The GGCT gene is located on chromosome 7p14-15 and consists of four exons that span 8 kb. The primary sequence is 188 amino acids in length and is unlike any protein of known function. We crystallized functional recombinant gamma-glutamyl cyclotransferase and determined its structure at 1.7 A resolution. The enzyme is a dimer of 20,994-Da subunits. The topology of GGCT is unrelated to other enzymes associated with cyclotransferase-like activity. The fold was originally classified as "BtrG-like," a small family that only includes structures of hypothetical proteins from Mus musculus, Escherichia coli, Pyrococcus horikoshii, and Arabidopsis thaliana. Since this is the first member of this family with a defined function, we propose to refer to this structure as the gamma-glutamyl cyclotransferase fold. We have identified a potential active site pocket that contains a highly conserved glutamic acid (Glu(98)) and propose that it acts as a general acid/base in the reaction mechanism. Mutation of Glu(98) to Ala or Gln completely inactivates the enzyme without altering the overall fold.


    Organizational Affiliation

    Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Gamma-glutamyl cyclotransferase
A, B
188Homo sapiensMutation(s): 1 
Gene Names: GGCT (C7orf24, CRF21)
EC: 4.3.2.9
Find proteins for O75223 (Homo sapiens)
Go to Gene View: GGCT
Go to UniProtKB:  O75223
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.201 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 34.926α = 90.00
b = 99.406β = 90.00
c = 99.948γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
REFMACrefinement
SCALEPACKdata scaling
MAR345dtbdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-10-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2017-10-25
    Type: Refinement description