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RESEARCH ARTICLE

You are what you secrete: extracellular proteins and virulence in Cryptococcus

Leona T Campbell A , Matthew P Padula B , Elizabeth Harry B and Dee A Carter A C
+ Author Affiliations
- Author Affiliations

A School of Molecular Bioscience, The University of Sydney, Sydney, NSW 2006, Australia

B iThree Institute, University of Technology, Sydney, NSW, Australia

C Corresponding author. Tel: +61 2 9351 5383, Email: dee.carter@sydney.edu.au

Microbiology Australia 36(2) 93-95 https://doi.org/10.1071/MA15030
Published: 1 May 2015

Abstract

Fungal organisms secrete a wide range of biomolecules, including degradative enzymes that are essential for nutrition, toxins, effectors and secondary compounds that modulate interactions with host animals and plants, and a variety of signaling and stress-related proteins. As these are likely to be key determinants of virulence and may also be useful diagnostic and therapeutic targets, we investigated the secretome of different strains of the fungal pathogen Cryptococcus. Virulent strains secreted predominantly hydrolytic and proteolytic enzymes, while the least virulent strain secreted a range of additional non-degradative proteins including many that lacked secretion signals, some that appear to be ‘moonlighting’, and a number that are known to be allergenic. It appears that in Cryptococcus, the secretome may influence virulence both through the presence of harmful enzymes and through the absence of proteins that alert the host defence mechanisms.


References

[1]  Girard, V. et al. (2013) Secretomes: the fungal strike force. Proteomics 13, 597–608.
Secretomes: the fungal strike force.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhtlagsbo%3D&md5=48af3b43644bbc24c95823263c372f76CAS | 23349114PubMed |

[2]  Springer, D.J. and Chaturvedi, V. (2010) Projecting global occurrence of Cryptococcus gattii. Emerg. Infect. Dis. 16, 14–20.
Projecting global occurrence of Cryptococcus gattii.Crossref | GoogleScholarGoogle Scholar | 20031037PubMed |

[3]  Byrnes, E.J. et al. (2010) Emergence and pathogenicity of highly virulent Cryptococcus gattii genotypes in the northwest United States. PLoS Pathog. 6, e1000850.
Emergence and pathogenicity of highly virulent Cryptococcus gattii genotypes in the northwest United States.Crossref | GoogleScholarGoogle Scholar | 20421942PubMed |

[4]  Chong, H.S. et al. (2012) Time-course proteome analysis reveals the dynamic response of Cryptococcus gattii cells to fluconazole. PLoS ONE 7, e42835.
Time-course proteome analysis reveals the dynamic response of Cryptococcus gattii cells to fluconazole.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhtFOltrbK&md5=a31809a706bff0052428958892d10207CAS | 22880118PubMed |

[5]  Huberts, D.H. and van der Klei, I.J. (2010) Moonlighting proteins: an intriguing mode of multitasking. Biochim. Biophys. Acta 1803, 520–525.
Moonlighting proteins: an intriguing mode of multitasking.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXjt1Gks7w%3D&md5=2c2d7542588777965990dd2b1b8ef956CAS | 20144902PubMed |

[6]  Eroles, P. et al. (1997) The highly immunogenic enolase and Hsp70p are adventitious Candida albicans cell wall proteins. Microbiology 143, 313–320.
The highly immunogenic enolase and Hsp70p are adventitious Candida albicans cell wall proteins.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2sXht1entbc%3D&md5=257be4e6bc200d88f6a870c864198399CAS | 9043108PubMed |

[7]  Gil-Navarro, I. et al. (1997) The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase of Candida albicans is a surface antigen. J. Bacteriol. 179, 4992–4999.
| 1:CAS:528:DyaK2sXlsVSmt7g%3D&md5=c9f16799a303b2b12fb0e2c3ae2c10c0CAS | 9260938PubMed |

[8]  Rodrigues, M.L. et al. (2008) Extracellular vesicles produced by Cryptococcus neoformans contain protein components associated with virulence. Eukaryot. Cell 7, 58–67.
Extracellular vesicles produced by Cryptococcus neoformans contain protein components associated with virulence.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXkvVGjtLw%3D&md5=7c0c5f1e7ccfc8dbd406ad7126a6c1f2CAS | 18039940PubMed |

[9]  Huang, S.-H. et al. (2012) Cryptococcus neoformans-derived microvesicles enhance the pathogenesis of fungal brain infection. PLoS ONE 7, e48570.
Cryptococcus neoformans-derived microvesicles enhance the pathogenesis of fungal brain infection.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhslehsrnF&md5=633fc6b9777857c6813ff2d825cf4000CAS | 23144903PubMed |

[10]  Casadevall, A. et al. (2003) ‘Ready made’ virulence and ‘dual use’ virulence factors in pathogenic environmental fungi - the Cryptococcus neoformans paradigm. Curr. Opin. Microbiol. 6, 332–337.
‘Ready made’ virulence and ‘dual use’ virulence factors in pathogenic environmental fungi - the Cryptococcus neoformans paradigm.Crossref | GoogleScholarGoogle Scholar | 12941400PubMed |

[11]  Engelthaler, D.M. et al. (2014) Cryptococcus gattii in North American Pacific northwest: whole-population genome analysis provides insights into species evolution and dispersal. mBio 5, e01464-14.
Cryptococcus gattii in North American Pacific northwest: whole-population genome analysis provides insights into species evolution and dispersal.Crossref | GoogleScholarGoogle Scholar | 25028429PubMed |

[12]  Billmyre, R.B. et al. (2014) Highly recombinant VGII Cryptococcus gattii population develops clonal outbreak clusters through both sexual macroevolution and asexual microevolution. mBio 5, e01494-14.
Highly recombinant VGII Cryptococcus gattii population develops clonal outbreak clusters through both sexual macroevolution and asexual microevolution.Crossref | GoogleScholarGoogle Scholar | 25073643PubMed |