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Structural characterization of purine nucleoside phosphorylase from human pathogen Helicobacter pylori

Zoran Štefanić1, Goran Mikleušević1, Marija Luić1

  • 1Division of Physical Chemistry, Ruđer Bošković Institute, POB 180, Bijenička cesta 54, HR-10002 Zagreb, Croatia.

International Journal of Biological Macromolecules
|March 25, 2017
PubMed

Insights

Researchers characterized Helicobacter pylori purine nucleoside phosphorylase (PNP), a key enzyme in its metabolism. Understanding this enzyme

Area of Science:

  • Biochemistry
  • Structural Biology
  • Microbiology

Background:

  • Helicobacter pylori is a significant human pathogen.
  • Increasing antibiotic resistance in H. pylori necessitates novel eradication strategies.
  • Purine metabolism in H. pylori relies on the salvage pathway, with purine nucleoside phosphorylase (PNP) as a key enzyme.

Purpose of the Study:

  • To perform basic biochemical and structural characterization of recombinant H. pylori PNP.
  • To investigate the enzyme's properties in the context of developing new anti-H. pylori drugs.

Main Methods:

  • Expression of recombinant H. pylori PNP in Escherichia coli.
  • Biochemical assays to determine enzyme activity.
  • Structural analysis of the H. pylori PNP enzyme.

Main Results:

  • The structure of H. pylori PNP is characteristic of high molecular mass PNPs.
  • The enzyme exhibits very low activity towards adenosine, similar to low molecular mass PNPs.
  • Basic biochemical and structural data for H. pylori PNP were obtained.

Conclusions:

  • The unique activity profile of H. pylori PNP warrants further investigation.
  • Understanding the molecular mechanism of H. pylori PNP could inform new drug development strategies.
  • Targeting H. pylori PNP may offer a novel approach for eradicating this pathogen.
Keywords:
Crystal structureHelicobacter pyloriPurificationPurine nucleoside phosphorylaseStabilitySubstrate specificity

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