[Metabolism of C(14)-glucose by Ascaridia galli]

Han Jong Rim1, Kwang Soo Kim, Soo Hyun Seong

  • 1Department of Parasitology and Institute of Endemic Diseasess, Korea.

Insights

This study reveals that the fowl nematode Ascaridia galli prioritizes glycogen synthesis over CO2 production when metabolizing glucose. This finding offers insights into parasitic worm glucose utilization and metabolism.

Area of Science:

  • Parasitology
  • Biochemistry
  • Molecular Metabolism

Background:

  • Ascaridia galli is a common fowl nematode impacting poultry health.
  • Understanding parasitic worm metabolism is crucial for developing targeted interventions.
  • Glucose metabolism pathways in A. galli have not been fully elucidated.

Purpose of the Study:

  • To quantitatively analyze glucose utilization by Ascaridia galli.
  • To determine the metabolic fate of glucose, specifically oxidation to CO2 and incorporation into glycogen.
  • To compare the rates of glucose oxidation versus glycogen synthesis in A. galli.

Main Methods:

  • Intact Ascaridia galli worms were incubated with C14-labeled glucose in Krebs-Ringer phosphate buffer.
  • Respiratory CO2 production and its specific activity were measured using a Geiger-Muller counter.
  • Glycogen concentration and turnover rates were determined in worm tissue samples.

Main Results:

  • A. galli exhibited a glucose uptake rate of 1.73 ± 0.32 μM/hr/g wet wt.
  • Total CO2 production averaged 8.44 ± 1.11 μM/hr/g wet wt., with 2.68 ± 0.38% originating from glucose.
  • Approximately 16.37 ± 4.04% of utilized glucose was incorporated into glycogen.

Conclusions:

  • At least 18.95% of utilized glucose contributes to either CO2 production or glycogen synthesis.
  • The synthetic process of incorporating glucose into glycogen is more active than its oxidative process into respiratory CO2 in A. galli.
  • Findings suggest a metabolic preference for glycogen storage over immediate energy production via oxidation in this nematode.

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