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Updated: Jul 11, 2026
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Recombinant Protein Expression, Crystallization, and Biophysical Studies of a Bacillus-conserved Nucleotide Pyrophosphorylase, BcMazG
Published on: May 16, 2017
A putative house-cleaning enzyme encoded within an integron array: 1.8 A crystal structure defines a new MazG subtype
Andrew Robinson1, Amy P Guilfoyle, Stephen J Harrop
1Department of Chemistry and Biomolecular Sciences, Macquarie University, NSW 2109, Australia.
Molecular Microbiology
|September 26, 2007
Summary
Mobile gene cassettes contain many unknown adaptive genes. Researchers identified a novel dNTP pyrophosphohydrolase (MazG) in a marine bacterium, potentially preventing DNA damage from non-canonical nucleotides.
Area of Science:
- Microbiology
- Molecular Biology
- Genomics
Background:
- Mobile gene cassettes represent a vast reservoir of uncharacterized genes with potential adaptive functions.
- The roles of most proteins encoded by these mobile elements remain unknown, particularly in non-clinical settings.
- Characterizing gene cassette arrays aids in understanding their genomic organization and functional potential.
Purpose of the Study:
- To characterize a novel protein encoded within a mobile gene cassette array from the marine bacterium Vibrio sp. DAT722.
- To elucidate the structure and enzymatic function of this putative MazG protein.
- To investigate the potential role of this protein in cellular house-cleaning and DNA integrity.
Main Methods:
- Genomic library screening to isolate and assemble a large gene cassette array.
- X-ray crystallography to determine the three-dimensional structure of the MazG protein.
- Biochemical assays to define the substrate specificity and enzymatic activity of the protein.
Main Results:
- The crystal structure of an alpha-helical MazG protein was solved, revealing distinct open and closed states.
- Functional assays identified the protein as a dNTP pyrophosphohydrolase with a preference for dCTP and dATP.
- The characterized protein is hypothesized to be involved in preventing the incorporation of damaging nucleotides into DNA.
Conclusions:
- The identified MazG protein from Vibrio sp. DAT722 represents a novel variant with dNTP pyrophosphohydrolase activity.
- This enzyme likely functions as a house-cleaning mechanism, safeguarding host-cell DNA integrity.
- The study highlights the functional potential of genes found within mobile genetic elements.
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