The Role of Extracellular Secreted Proteases and Phospholipases Enzymes in Differentiation Between Pathogenic and Non-Pathogenic Candida.

Abstract

The genus Candida contains approximately 200 species. All humans are colonized with Candida species, mostly Candida albicans, yet some develop diseases due to Candida, among which genitourinary manifestations are extremely common. The aim of this study was to differentiate between pathogenic and non-pathogenic Candida according to extracellular protease and phospholipase activities. Specimens were cultured on Sabouraud dextrose agar for 24 h then sub cultured on Sabouraud dextrose broth for 24 h at 37 oC, then the broth media was centrifuged and the enzyme activity was determined in the supernatant. Five pathogenic isolates were checked quantitively for their ability to produce different extracellular enzymes. Purified C.albicans had maximum protease activities (105.67 ± 3.66 U/ml/hr). The other pathogenic species showed an extracellular protease activities range from (86 ± 2.7 to 100.75 U/ml/hr). Purified C. glabrata had the maximum phospholipase activities (2.64 ± 0.192 μmol/hr) while other pathogenic species showed an extracellular phospholipase activities rang from (1.62 ± 0.21 to 2.28 ± 0.156 μmole/hr). On the other hand, extracellular protease and phopholipase enzymes had significant lower activity in the non-pathogenic species. So, the extracellular proteases and phospholipase activity could be used as a diagnostic tool to differentiate between pathogenic and non-pathogenic Candida.