Differential expression of Candida dubliniensis-secreted aspartyl proteinase genes (CdSAP1-4) under different physiological conditions and during infection of a keratinocyte culture

• Published in: FEMS immunology and medical microbiology Vol. 56; no. 3; pp. 212 - 222
• Main Authors: Loaiza-Loeza, Salomé, Parra-Ortega, Berenice, Cancino-Díaz, Juan Carlos, Illades-Aguiar, Berenice, Hernández-Rodríguez, César Hugo, Villa-Tanaca, Lourdes
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.08.2009; Blackwell Publishing Ltd; Blackwell; Oxford University Press
• Subjects: Albumins; Aspartic Acid Endopeptidases - biosynthesis; Aspartic endopeptidase; Biological and medical sciences; Candida - enzymology; Candida albicans; Candida dubliniensis; Cell culture; Cell Line; E.C.3.4.23; Enzyme Inhibitors - pharmacology; Fundamental and applied biological sciences. Psychology; Fungal Proteins - biosynthesis; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Fungal; Genes; Genomes; Humans; Hydrogen-Ion Concentration; Infections; keratinocyte infection; Keratinocytes; Keratinocytes - microbiology; Microbiology; Miscellaneous; Mycelia; Mycology; Nitrogen; Nitrogen metabolism; Pepstatins - pharmacology; pH effects; Phylogeny; Protease inhibitors; Proteinase; Proteinase inhibitors; SAP genes; secreted aspartyl protease; Secreted aspartyl proteinase; Sequence Homology, Amino Acid; Virulence; Virulence factors; Yeast; Yeasts; keratinocyte infection; secreted aspartyl protease; genes; E.C.3.4.23; Ascomycota; Candidiasis; Yeast; Mycosis; Microbiology; Enzyme; Secretion; SAPgenes; Fungi; Infection; Peptidases; Immunology; Gene; Hydrolases; Keratinocyte; Candida dublimensis; Candida dubliniensis
• ISSN: 0928-8244; 1574-695X; 2049-632X
• DOI: 10.1111/j.1574-695X.2009.00570.x

The in vitro and keratinocyte (HaCAT cells) culture expression of four putative genes coding for secreted aspartyl proteases of Candida dubliniensis-CdSAP1, CdSAP2, CdSAP3, and CdSAP4 (CdSAP1-4) - is reported for the first time. In addition, CdSAP7, 8, 9, and 10, orthologous genes of Candida albicans, were recognized in C. dubliniensis genome. There are no orthologs of C. albicans SAP5 and 6 in C. dubliniensis. The expression of CdSAP1 and 2 was independent of the morphological stage of C. dubliniensis; they are expressed at both pH 4 and pH 7, and were induced with albumin as nitrogen source. CdSAP3 expression was regulated by the pH, and was related to the infection process of keratinocytes. Expression of CdSAP4 predominated during the mycelial phase and the initial stage of keratinocyte infection. During infection of the HaCaT cell line, only genes CdSAP3-4 were expressed, and keratinocytes were affected in their number and shape by the infection with C. dubliniensis; however, this effect decreased in the presence of pepstatin A (aspartyl protease inhibitor). Pepstatin A was not able to inhibit keratinocyte damage. Based on the aforementioned, we suggest that the Saps from C. dubliniensis could be considered a virulence factor just as those from C. albicans, and participants in the nitrogen metabolism of the yeast for nutrient acquisition.