Considerações sobre eventos celulares em espécies de Candida expostas à piocianina

Abstract

Ecological interactions enable the transfer of molecular and genetic information between microorganisms, being crucial for their establishment and development in a variety of environments. The literature reports that Pseudomonas aeruginosa, a cosmopolitan bacillar bacterium, is able to interact with the environment and other microorganisms, including yeasts, through its metabolites, highlighting pyocyanin, a pigment linked to its virulence. The aim of this work was to verify cellular alterations promoted by pyocyanin exposure in four yeasts: Candida albicans ATCC 76485, C. parapsilosis ATCC 22019, C. tropicalis ATCC 13803 and C. krusei ATCC 6258. For this purpose, in vitro tests were carried out on the action of pyocyanin in the: Minimal Inhibition Concentration (MIC) and Minimum Fungicide Concentration (CFM); cell viability; damage to the cell wall and membrane; surface adhesion and disturbance of mature biofilm. The pyocyanin MIC was 600 μg/mL for all tested strains. On the other hand, CFM was 1.200 μg/mL for C. albicans ATCC 76485, C. parapsilosis ATCC 22019 and > 1.200 μg/mL for C. tropicalis ATCC 13803 and C. krusei ATCC 6258. Pyocyanin promoted damage to the cell wall and did not interfere with the membrane. The cell viability after 48h of pigment exposure was 7.69% (C. albicans ATCC 76485), 13.62% (C. tropicalis ATCC 13803), 10.83% (C. parapsilosis ATCC 22019) and 2.19 % (C. krusei ATCC 6258). In addition, pyocyanin interfered in the adhesion of C. tropicalis ATCC 13803, whereas in the other strains, cell adhesion and stablished biofilm were not affected. The results suggest that the interaction between Candida spp. and P. aeruginosa may be antagonistic, however, yeasts may exhibit mechanisms to ensure their permanence when the pigment is present