The Library
The Ultimate On-line Candida Resource
Glossary    Contact Us
 
   
Browse by Category
Your Are Here >> Library Home > Candida In The Body > How Candida Affects Us > Profile of Candida albicans-Secreted Aspartic Proteinase Elicited during Vaginal Infection

Back

We'd love to hear from you - the Candida Library is for you. Let us know if you have any suggestions, ideas or feedback. Click here to email us.

Profile of Candida albicans-Secreted Aspartic Proteinase Elicited during Vaginal Infection

Profile of Candida albicans-Secreted Aspartic Proteinase Elicited during Vaginal Infection.
Brad N. Taylor, Peter Staib, Ayfer Binder, Antje Biesemeier, Miriam Sehnal, Martin Röllinghoff, Joachim Morschhäuser, and Klaus Schröppel


"Vaginal infections caused by the opportunistic yeast Candida albicans are a significant problem in women of child-bearing age. Several factors are recognized as playing a crucial role in the pathogenesis of superficial candidiasis; these factors include hyphal formation, phenotypic switching, and the expression of virulence factors, including a 10-member family of secreted aspartic proteinases. Candida albicans is a common commensal fungal organism that is part of the normal microflora of the genital and gastrointestinal tract of healthy individuals. Under appropriate conditions, C. albicans can become an opportunistic pathogen that has debilitating and sometimes deadly consequences for its host. One common manifestation of Candida infection is superficial candidiasis, which is a significant problem encountered in clinics worldwide. The most common superficial infections are vaginal candidiasis and mucosal candidiasis of the oropharyngeal cavity and the esophagus. Several factors of C. albicans were previously identified as virulence determinants; these factors include hyphal formation, phenotypic switching, and secretion of hydrolytic enzymes. Although hyphal formation is probably the best-documented virulence determinant of C. albicans, the production of hydrolytic enzymes, specifically the secreted aspartic proteinases (Saps), as key virulence determinants has been comprehensively studied. Ten SAP isogenes encode the Sap proteins. The purported functions of Saps during infection include the digestion of host proteins for nutrient supply, evasion of host defenses by degradation of immunoglobulins and complement proteins, adherence, and degradation of host barriers during invasion. Due to their wide substrate specificity and broad pH range, it is accepted that Saps contribute to the development of active Candida infections".



ABSTRACT
Vaginal infections caused by the opportunistic yeast Candida albicans are a significant problem in women of child-bearing age. Several factors are recognized as playing a crucial role in the pathogenesis of superficial candidiasis; these factors include hyphal formation, phenotypic switching, and the expression of virulence factors, including a 10-member family of secreted aspartic proteinases. In the present investigation, we analyzed the secreted aspartic proteinase gene (SAP) expression profile of C. albicans that is elicited in the course of vaginal infection in mice and how this in vivo expression profile is associated with hyphal formation. We utilized two different genetic reporter systems that allowed us to observe SAP expression on a single-cell basis, a recombination-based in vivo expression technology and green fluorescent protein-expressing Candida Of the six SAP genes that were analyzed (SAP1 to SAP6), only SAP4 and SAP5 were detectably induced during infection in this model. Expression of both of these genes was associated with hyphal growth, although not all hyphal cells detectably expressed SAP4 and SAP5. SAP5 expression was induced soon after infection, whereas SAP4 was expressed at later times and in fewer cells compared with SAP5. These findings point to a link between morphogenetic development and expression of virulence genes during Candida vaginitis in mice, where host signals induce both hyphal formation and expression of SAP4 and SAP5, but temporal gene expression patterns are ultimately controlled by other factors. reporter strains.

Full Article:

http://iai.asm.org/cgi/content/full/73/3/1828?view=long&pmid=15731084






Keywords: vaginal infections yeast candida albican candidasis fungal mucosal candidiasis virulence saps hyphal growth virulence genes vaginitis

Rate This Article: