Among potential virulence factors of Candida albicans, enzymes seem to play an important role. Many studies concern the secreted aspartic proteinases (saps), and the degradation of some components of the subendothelial extracellular matrix by the isoenzyme sap2 has been proved. Nevertheless, other proteolytic enzymes could be involved in the pathogenicity of the yeast. We studied the degradation of four constitutive proteins of the extracellular matrix: type I and IV collagens, laminin and fibronectin, by a 95-kDa metallopeptidase, localised in the cell wall of C. albicans. Each of these constituents was incubated with the purified enzyme and its degradation products analysed by an electrophoretic method. We observed that type I collagen and fibronectin were totally degraded by the enzyme whereas type IV collagen and laminin were only partially degraded. The C. albicans metallopeptidase may play a role in the degradation of the subendothelial extracellular matrix components. This enzyme could facilitate the migration of the yeast in the tissues after crossing the endothelial layer, allowing the fungal invasion of target organs.

Some carbohydrates are known to decrease the attachment of Acanthamoeba sp. to biological surfaces. By a method based on the reduction of a tetrazolium salt (XTT) by the mitochondrial dehydrogenases of the parasites, d-mannose and alpha-d-mannopyranoside have been shown to reduce Acanthamoeba attachment to inert surfaces, indicating that the mannose binding protein of Acanthamoeba trophozoites is involved in adherence to inert surfaces. The reduction in attachment is dose dependant and is not linked with a potential toxicity of the carbohydrates. All the species of Acanthamoeba tested were concerned by this mannose binding protein, but the adhesion of A. culbertsoni was also reduced by the presence of glucose.

Some carbohydrates are known to decrease the attachment of Acanthamoeba sp. to biological surfaces. By a method based on the reduction of a tetrazolium salt (XTT) by the mitochondrial dehydrogenases of the parasites, d-mannose and alpha-d-mannopyranoside have been shown to reduce Acanthamoeba attachment to inert surfaces, indicating that the mannose binding protein of Acanthamoeba trophozoites is involved in adherence to inert surfaces. The reduction in attachment is dose dependant and is not linked with a potential toxicity of the carbohydrates. All the species of Acanthamoeba tested were concerned by this mannose binding protein, but the adhesion of A. culbertsoni was also reduced by the presence of glucose.