A MANNOSE-BINDING LECTIN DISPLAYS Candida GROWTH INHIBITION AND ADHESION REDUCTION TO HOST CELLS

DEL RIO M; DE LA CANAL L; NAVARRO M; PINEDO M; MORA H; REGENTE M

Mar del Plata

Congreso; LI Congreso de la Sociedad Argentina de Investigación Bioquímica; 2015

Sociedad Argentina de Investigación Bioquímica

Candida cell wall consists of a skeleton of glucans and chitin, with an outer layer enriched in mannoproteins. Lectinscan show antimicrobial abilities through their interaction with glycoconjugates on pathogen surfaces. We havedescribed a sunflower mannose-binding lectin (Helja), which inhibits the growth of C. parapsilosis. The aim of thiswork was to assess the Helja effect on C. guillermondii (Cg) growth and its adhesion to host cells, and to explore theinteraction of the lectin with the outer N- and O-mannoproteins, using yeast mutants with specific mannosylationdefects. Helja (100 μg/mL) was able to reduce by 75 % the growth of the wt strain. To determine the contribution ofthe fungal mannosylation on Helja effect, we used a Cg pmr1Δ null mutant, which displays both O- and N-mannanseverely truncated. This strain showed similar growth inhibition in the presence of Helja than wt yeast. The lectin wasalso tested for its effect on Cg adhesion to buccal epithelial cells, detecting a significant binding reduction of wt strainto these cells. However, the pmr1Δ mutant showed similar levels of adhesion both in the presence and absence ofHelja. Thus, the nature and extent of Cg mannosylation appear to be essential for Helja interference on fungaladhesion to host cells, but the mannan defect assessed is not sufficient to bypass the growth inhibition displayed bythis lectin.