Biocontrol potential of the Lactiplantibacillus -derived protein SDZ3-1 for Candida albicans biofilm through the MAPK signalling pathway

Candida albicans is the most common opportunistic pathogenic fungus responsible for contamination in foods; especially when biofilm is formed, the difficulty of removal increases dramatically. The MBIC80 and MBEC50 of SDZ3‑1, a protein isolated from Lactiplantibacillus plantarum ALAC‑6, against biofilm of C. albicans were 160 μg/mL. Treatment with 0.25 × MBIC80 SDZ3‑1 significantly reduced cell surface hydrophobicity to 0.365 (p < 0.001), increased potassium ion release to 1.303 ± 0.087 mg/kg (p < 0.01), inhibited hyphal growth and induced exudate formation on the hyphal surface. These results indicate that SDZ3‑1 impairs biofilm formation through inhibition of adhesion, hyphal development and structural integrity. Transcriptome analysis revealed that SDZ3-1 down-regulated genes related to adhesion and the Mitogen-Activated Protein Kinase (MAPK) signalling pathway of filamentation (Ste11, Kss, Tec1, Ste7 and Ste12). Overall, the results show that SDZ3-1 can effectively inhibit and remove biofilm, making it a promising candidate for combating C. albicans biofilm.