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Updated: May 19, 2026
08:38
Using a Bacterial Pathogen to Probe for Cellular and Organismic-level Host Responses
Published on: February 22, 2019
Lichtheimia species exhibit differences in virulence potential.
Volker U Schwartze1, Kerstin Hoffmann, Ildikó Nyilasi
1Department of Microbial Pathogenicity Mechanisms, Hans Knöll Institute, Jena, Germany.
Plos One
|August 23, 2012
Summary
Lichtheimia species cause mucormycosis, but their virulence varies. This study found that only clinically relevant Lichtheimia species showed full virulence in chicken embryos, suggesting distinct pathogenic potentials.
Area of Science:
- Medical Mycology
- Fungal Pathogenesis
- Zoonotic Diseases
Background:
- Mucormycosis cases are rising, yet the virulence of most mucoralean fungi remains poorly understood.
- Lichtheimia species are significant causes of mucormycosis globally, but only some species are linked to human infections.
- It is unclear if observed clinical differences in mucormycosis are due to fungal virulence or other factors.
Purpose of the Study:
- To investigate the virulence of all five Lichtheimia species and related Dichotomocladium species.
- To determine if clinical relevance correlates with fungal virulence.
- To explore factors influencing fungal virulence, such as environmental origin, phylogenetic position, and physiological traits.
Main Methods:
- Tested virulence of 46 Lichtheimia strains (all five species) and Dichotomocladium strains in a chicken embryo model.
- Analyzed origins (environmental vs. clinical) and phylogenetic positions of tested strains.
- Conducted physiological studies on stress resistance and carbon source utilization.
Main Results:
- Full virulence was observed only in clinically relevant Lichtheimia species; L. hyalospora, L. sphaerocystis, and Dichotomocladium species showed attenuated virulence.
- No correlation was found between virulence and the origin or phylogenetic position of strains within species.
- Physiological factors like stress resistance and carbon source utilization did not consistently explain virulence differences, though slower growth at 37°C was noted in less virulent strains.
Conclusions:
- The clinical presentation of mucormycosis likely reflects inherent differences in the virulence potential among Lichtheimia species.
- Factors beyond simple growth rate at host temperature influence fungal virulence.
- Further research is needed to elucidate the complex interplay of factors determining Lichtheimia virulence.
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