[Dynamic monitoring and analysis of the persisters emerging in Candida albicans biofilm].

PURPOSE: To investigate the mechanism and approach related to persisters emerging in Candida albicans biofilm by studying its dynamic characteristics. METHODS: The Candida albicans biofilms model in vitro were formed by individual yeast cells and hyphal compartments respectively. The numbers of progenitive fungal cells and persisters at different stages were counted and analyzed with SPSS11.5 software package. The biofilm morphological changes were observed under confocal scanning laser microscopy. RESULTS: Different stages of biofilms which were formed by individual yeast cells and hyphal compartments had no significant difference both on the number of progenitive fungal cells and persisters. The number of progenitive fungal cells showed S-shaped growth curve until 12 hours. The persisters emerged within 0.5 hour and its number reached a steady state after 2 hours while the biofilm was in the period of microcolony formation under microscopy. CONCLUSIONS: The persisters emerging in Candida albicans biofilm are closely connected with the attachment to a surface(within 2 hours of the biofilm formation) and have little association with the maturity of the biofilm and its dimorphism.

[The construction and expression of Saccharomyces albicans pACT1-GFP plasmids].

OBJECTIVE: To construct strains containing green fluorescent protein (GFP) to study gene regulation in Saccharomyces albicans cells during the infection process. METHODS: pACT1-GFP was constructed, and Saccharomyces albicans CAI4 was transformed. The expression of GFP in yeast and hyphal compartments was observed with microscopy. RESULTS: 99% of Saccharomyces albicans cells containing pACT1-GFP fusion displayed significant fluorescence levels both in the yeast and hyphal compartments. The fluorescence intensity in two compartments had no obvious difference. CONCLUSION: pACT1-GFP can be expressed stably in the yeast cells.