Candida parapsilosis growth inhibitory activity of a mannose-binding lectin. Role of the fungal cell wall mannans.

PÉREZ GARCÍA, LA; REGENTE, MC; DE LA CANAL, L; MORA, H; DEL RÍO, M.; PINEDO, M.

Villa General Belgrano, Córdoba

Simposio; 2nd Argentinean Symposium of Glycobiology; 2016

Candida parapsilosis growth inhibitory activity of a mannose-binding lectin. Role of the fungal cell wall mannans. Candida spp. are the most frequent opportunistic fungal pathogens of humans, causing superficial mycosis and life threatening systemic infections in immunocompromised patients. Its cell wall is enriched with mannoproteins that have significant roles in the cell integrity, adhesion and virulence. We have described a sunflower mannose-binding lectin (Helja), which shows antimycotic effect on some members of Candida genus. The aim of this work was to assess the ability of recombinant Helja on C. parapsilosis (Cp) growth and adhesion to buccal epithelial cells (bec), through the comparison of its effect on wild type (wt) and mutant strains with specific mannosylation defects. Our results show that Helja 200 μg/ml was able to reduce by 40 % the wt yeast proliferation. A similar growth inhibition was observed in the och1∆ null mutant, which displays severely truncated N-mannans at the cell surface. On the other hand, the och1∆ mutant showed similar levels of adhesion to bec both in the absence and presence of Helja, while the wt exhibited reduced adhesion when the lectin was present. These results indicate that the integrity of C. parapsilosis glycosylation appear to be required for Helja interference on fungal adhesion while the mannosylation defect of the mutant och1∆ is not sufficient to block the proliferation inhibition exhibited by the lectin. The impact of the interaction of Helja with outer mannoproteins on its antifungal and anti-adhesion activity will be discussed.