tropicalis secretes high levels of Saps in a medium containing

bovine serum albumin as the sole source of nitrogen.[41] Sap expression in C. tropicalis during colonization of the oral epithelium is not associated with invasion and tissue damage.[51] Sap production has been studied preferentially in C. albicans and few reports have been found on Sap production Mitomycin C mw of non-albicans Candida spp. It is believed that there is a correlation between the expansion of SAP genes and the transition from commensal to pathogenic microorganisms. Non-pathogenic Candida spp. usually have fewer genes encoding Sap than opportunistic pathogenic species and this fact can be confirmed by gene sequencing these strains. However, this rule cannot be applied to species such as C. glabrata or C. krusei, which do not possess any SAP genes.[44] SAP genes are differentially involved in the development and maintenance of infections.[21] Expression of SAP1–SAP3 appears to be essential in mucosal infections and SAP4–SAP6 expression is essential in systemic infections.[21, 52, 53] The proteinases encoded by SAP9 and SAP10 appear to play a role in cell integrity, adhesion and cell separation after budding. In an infected host, Candida spp. are found in both hyphae and yeast forms. It is believed that hyphae formation is essential for fungal invasion, HM781-36B concentration as it assists in

the escape from the macrophage after phagocytosis.[41, 54] Some studies crotamiton in vitro have reported that SAP1–SAP3 are expressed in the yeast phase, whereas SAP4–SAP6 are expressed only in the hyphal phase (Fig. 2).[41, 55-58] It is believed that SAP2 has a functional role in invasion and spread of systemic infections.[52, 58, 59] The expression of these genes and the development of hyphae are not strictly linked, but are governed

by the same factors.[41] A further study on substrate specificity of Sap isoenzymes conducted by Aoki et al. [61] showed similar specificity among them. They were clustered into three groups according to substrate specificity. Sap7 and Sap10 showed high substrate specificity, whereas other Sap isoenzymes had broad substrate specificity. Interestingly, Sap4 to Sap6, which are coproduced in the hyphal form, may target similar host proteins. According to Ortega et al. [44], the pattern of SAP gene expression can be modified depending on the exposure conditions of the isolates. Physiological stress seems to promote increased secretion of Sap. Gene expression is variable and may be influenced by environmental conditions in vivo and by experimental conditions in vitro. Results of a study by White and Agabian [20] suggest that the cellular type controls the expression pattern of Sap isoenzymes. Studies on SAP gene expression identified seven genes as being differentially regulated in vitro (Fig.