2Q5Z: Crystal Structure Of Imazg From Vibrio Dat 722: Ntag-Imazg (P43212)

Mobile gene cassettes collectively contain a highly diverse pool of novel genes that encode many novel adaptive functions. In the non-clinical context, the function of almost all of the encoded proteins remains unknown despite the enormous size of this mobile gene pool. We have been characterizing cassette arrays by taking advantage of the fact that they cluster at discrete sites in chromosomes; even large arrays are thus recoverable in a relatively small number of clones in genomic libraries. In one assembled array of 116 cassettes from the marine bacterium Vibrio sp. DAT722, a putative MazG protein is encoded within the 21st cassette. Because MazG proteins are implicated in a number of cellular processes, including house-cleaning and stress survival, the presence of such a protein in a mobile cassette was noteworthy. Here we solve the crystal structure of this alpha-helical protein, and define both open and closed states of a new variant of the MazG family. Functional assays confirm that the protein is a dNTP pyrophosphohydrolase, with marked preferences for dCTP and dATP. We hypothesize that iMazG acts as a house-cleaning enzyme, preventing the incorporation of damaging non-canonical nucleotides into host-cell DNA.
PDB ID: 2Q5ZDownload
MMDB ID: 59386
PDB Deposition Date: 2007/6/4
Updated in MMDB: 2007/11
Experimental Method:
x-ray diffraction
Resolution: 2.3  Å
Source Organism:
Similar Structures:
Biological Unit for 2Q5Z: tetrameric; determined by author and by software (PISA,PQS)
Molecular Components in 2Q5Z
Label Count Molecule
Proteins (4 molecules)
Hypothetical Protein
Molecule annotation
Chemicals (8 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB