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Catalase and Ascorbate Peroxidase in Euglenozoan Protists.

Ingrid Škodová-Sveráková1,2, Kristína Záhonová1,3, Barbora Bučková2

  • 1Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 370 05 České Budějovice (Budweis), Czech Republic.

Pathogens (Basel, Switzerland)
|April 30, 2020
PubMed
Summary
This summary is machine-generated.

Euglenozoa utilize catalase and ascorbate peroxidase for detoxification, with evidence of horizontal gene transfer for catalase and unique adaptations for ascorbate peroxidase. These enzymes are recruited for specialized functions like photosynthesis and membrane-bound activity.

Keywords:
Euglenozoaascorbate peroxidasecatalaseenzymatic activityphylogeny

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Area of Science:

  • Biochemistry
  • Evolutionary Biology
  • Molecular Biology

Background:

  • Reactive oxygen species (ROS) are damaging molecules central to cellular function.
  • Catalase (CAT) and ascorbate peroxidase (APX) are key enzymes in ROS detoxification pathways.
  • Euglenozoa represent a diverse eukaryotic clade with varied lifestyles, including free-living and parasitic forms.

Purpose of the Study:

  • To investigate the biochemical properties and evolutionary histories of CAT and APX in Euglenozoa.
  • To understand the roles of these enzymes in different Euglenozoa lineages.
  • To explore mechanisms of enzyme acquisition, such as horizontal gene transfer.

Main Methods:

  • Phylogenetic analysis of CAT and APX genes across Euglenozoa.
  • Comparative analysis of enzyme biochemical properties.
  • Bioinformatic approaches to identify gene origins and evolutionary events.

Main Results:

  • Evidence for multiple independent horizontal gene transfer (HGT) events for CAT acquisition in Euglenozoa.
  • Identification of unique evolutionary innovations associated with APX presence in specific lineages.
  • Functional recruitment of CAT and APX for distinct roles, including photosynthesis and membrane-bound peroxidase activity.

Conclusions:

  • Euglenozoa exhibit diverse evolutionary strategies for acquiring and utilizing ROS detoxification enzymes.
  • HGT plays a significant role in shaping the CAT repertoire within this clade.
  • APX has undergone lineage-specific adaptations, suggesting specialized functional roles in Euglenozoa.