Analysis of virulence factors andin vivobiofilm-forming capacity ofYarrowia lipolyticaisolated from patients with fungemia

Abstract

Yarrowia lipolytica is ubiquitous in the environment, opportunistic, and might be considered as one of the causative agents of catheter-related candidemia. Our work aimed to study some virulence factors of Y. lipolytica such as hydrolases production and biofilm formation with comparison to the most frequent Candida specie in human disease. In sum, 58 clinical isolates of Y. lipolytica, 16 C. glabrata, and 12 C. albicans were collected from Intensive care unit (ICU). All were tested for enzymatic production and biofilm formation. All tested isolates of C. albicans and C. glabrata were able to degrade casein, and 98.2% of Y. lipolytica showed caseinase activity but no gelatinase activity was detected in all isolates. Y. lipolytica strains showed significantly lower (3.4%) in vitro phospholipase activity than C. albicans and C. glabrata (P < .05). No significant differences of the hemolytic activity were detected between the three species (P > .05). Concerning biofilm formation, and unlike the results obtained on polystyrene plate, the number of adhered and biofilm cultivable cells obtained by Y. lipolytica after 168 hours of catheter subcutaneous implantation is significantly greater and tends to be more compact and structured hyphal layer. Although C. albicans remains the most pathogenic yeast, development of selective ability of Y. lipolytica to adhere, to form a biofilm on catheter medical devices, and to produce phospholipase and hemolytic enzyme is of particular interest, and it is strongly recommended to be vigilant in the use of medical implanted medical devices, particularly in ICU.

Relationship between the Antifungal Susceptibility Profile and the Production of Virulence-Related Hydrolytic Enzymes in Brazilian Clinical Strains ofCandida glabrata

“…Caseinase activity was not detected under the employed experimental conditions for any of the tested C. glabrata strains. However, these results were discordant from those found by Abbes et al [53] who reported caseinase activity in 16 C. glabrata isolates. Secretion of caseinase has also been observed in Candida parapsilosis sensu stricto [24], Candida haemulonii species complex [54], and Yarrowia lipolytica [53].…”

“…However, these results were discordant from those found by Abbes et al [53] who reported caseinase activity in 16 C. glabrata isolates. Secretion of caseinase has also been observed in Candida parapsilosis sensu stricto [24], Candida haemulonii species complex [54], and Yarrowia lipolytica [53]. Pärnänen et al [55] identified a serine protease in C. glabrata linked to the fungal cell wall, but its role in virulence of C. glabrata remains uncertain.…”

Yarrowia lipolytica: a beneficious yeast in biotechnology as a rare opportunistic fungal pathogen: a minireview

“…Hydrolytic enzymes are one of the major factors, which could affect the pathogenicity of Y. lipolytica . This fungus is able to produce wide range of hydrolases, such as: proteases, phospholipases and hemolysins, which help in the invasion of tissues (Abbes et al 2017 ; Kantarcioglu and Yucel 2002 ). Phospholipases and proteases secreted by yeasts play an important role in the damage of cell membranes, which consist of lipids and proteins.…”

“…In another research 58 Y. lipolytica isolates of blood, urine and vaginal origin were evaluated to produce hydrolytic enzymes in comparison with C. albicans and C. glabrata . 98.2% of Y. lipolytica isolates showed caseinase activity and only vaginal isolates showed phospholipase activity and the hemolytic activity between the three species showed no significant differences (Abbes et al 2017 ).…”

“…D’Antonio et al ( 2002 ) reported that Y. lipolytica produced large amount of slime in glucose-based medium and that confirms the ability of biofilm production and also adhesion to and colonization of plastic central venous catheter. Abbes et al ( 2017 ) studied biofilm formation by Y. lipolytica in comparison with C. albicans and C. glabrata . Biofilms development have been examined in vitro (using 96-well polystyrene microtiter plates) as well as in vivo in a rat subcutaneous model.…”