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A link between urease and polyamine metabolism in Cryptococcus neoformans
Barbra Toplis1, Caylin Bosch1, Marietjie Stander2
1Department of Microbiology, University of Stellenbosch, Matieland, 7602, Stellenbosch, South Africa.
Microbial Pathogenesis
|July 3, 2021
Summary
Cryptococcus neoformans urease influences polyamine metabolism, affecting biogenic amine production. Urease deficiency alters polyamine levels and confers resistance to inhibitors, revealing urease
Area of Science:
- Microbiology
- Biochemistry
- Yeast Metabolism
Background:
- The urease enzyme in Cryptococcus neoformans connects to metabolic pathways, including polyamine metabolism.
- Cryptococcal biogenic amine production and its link to urease remain largely uninvestigated.
Purpose of the Study:
- To investigate and compare polyamine metabolism in wild-type, urease-negative, and urease-reconstituted Cryptococcus neoformans strains.
Main Methods:
- Mass spectrometry was employed to analyze polyamine profiles.
- Comparative analysis of wild-type and urease-deficient mutants under varying temperatures (26°C and 37°C).
- Assessment of polyamine inhibitors (cyclohexylamine and DL-α-difluoromethylornithine) and the effect of polyamine supplementation.
Main Results:
- Agmatine and spermidine identified as major polyamines, with temperature-dependent variations.
- Urease deficiency altered extracellular and intracellular polyamine ratios (putrescine, spermidine, agmatine).
- Urease-deficient mutants showed reduced susceptibility to polyamine inhibitors, with effects more pronounced at 37°C.
- Polyamine supplementation alleviated growth inhibition caused by inhibitors.
Conclusions:
- This study provides novel insights into Cryptococcus neoformans polyamine metabolism.
- Urease plays a significant role in the production of biogenic amines in C. neoformans.
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