BIood Lysate Staining, a New Microscopic Method for Diagnosis of Fungemia Using Peripheral Blood
Proteolytic activity of medically important yeasts was tested in both YCB-BSA agar and medium. All of 134 strains of <i>Candida albicans</i>, 13 of 18 strains of <i>Candida tropicalis</i> and 11 of 18 strains of <i>Candida parapsilosis</i> had this activity, while none of 52 <i>Candida glabrata</i> strains or of 11 <i>Cryptococcus neoformans</i> strains tested had proteolytic activity. Strains of <i>C. albicans</i> fell into five groups based on the level and time-course of <i>in vitro</i> proteinase productivity. Five strains randomly selected from each group were tested for pathogenicity in mice. The strain possessing the strongest pathogenicity was used to purify proteinase. The molecular weight of the proteinase was approximately 44, 000 daltons and its isoelectric point was pH 4.2. Optimal pH of the proteinase was 3.2 and the enzyme was stable below pH 7.0 and lost its activity above pH 8.0 at 37C in a 60-min incubation. The 23 amino acid sequence of the proteinase N-terminus was determined.
- Microbiology and immunology
Microbiology and immunology 44(8), 637-641, 2000-08-20
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