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Updated: Jul 9, 2026
08:24
Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans
Published on: February 27, 2018
Extracellular vesicles produced by Cryptococcus neoformans contain protein components associated with virulence
Marcio L Rodrigues1, Ernesto S Nakayasu, Debora L Oliveira
1Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, 21941590 Rio de Janeiro, Brazil.
Eukaryotic Cell
|November 28, 2007
Summary
Cryptococcus neoformans secretes virulence factors via extracellular vesicles. These "virulence bags" deliver fungal products, like glucuronoxylomannan, to host tissues, aiding cryptococcosis pathogenesis.
Area of Science:
- Mycology
- Microbiology
- Pathogenesis
Background:
- Cryptococcus neoformans is a fungal pathogen causing cryptococcosis.
- The fungus produces glucuronoxylomannan (GXM), a major virulence factor.
- Extracellular vesicles are implicated in GXM secretion.
Purpose of the Study:
- To characterize the morphology and protein composition of C. neoformans secretory vesicles.
- To investigate the role of these vesicles in fungal pathogenesis.
Main Methods:
- Electron microscopy for vesicle morphology.
- Proteomics for protein identification.
- Enzymatic assays and serological reactivity tests.
Main Results:
- Vesicles exhibit diverse morphologies and sizes.
- Seventy-six proteins identified, including virulence and oxidative stress-related factors.
- Vesicles possess laccase and urease activities and are recognized by patient sera.
Conclusions:
- C. neoformans utilizes extracellular vesicles for efficient secretion of pathogenesis-related molecules.
- These vesicles act as
- virulence bags
- delivering concentrated fungal payloads to hosts.
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