Recombinant AMPs (Epinecidin-1 and its Variants): A New Hope against Invasive Fungal Infections against Candida spp....

To enhance stability and antimicrobial efficacy of antimicrobial peptide (AMP) epinecidin-1, we previously engineered three variants - GK-epi-1, Variant-1 and Variant-2-by substituting alanine and histidine residues with lysine. Our current study focuses on the antifungal capabilities of Epinecidin-1 and its variants against the clinical isolates of Candida spp. (Candida albicans, C. tropicalis, C. krusei & C. glabrata) and Aspergillus flavus. Computational docking studies are evidenced, the peptides had strong affinity against all fungal receptor examined which indicates their efficacy to interact with the Candida cell membrane receptors (Exo-B-(1,3)-Glucanase, Secreted aspartic proteinase (SAP) 1 & N-terminal domain adhesin: Als 9 - 2). Minimum Inhibitory Concentration (MIC), Minimum Fungicidal Concentration (MFC) and antibiofilm assays revealed its potent antifungal activity, particularly in disrupting biofilm formation. Effects of peptides on hyphal growth inhibition activity and Scanning Electron Microscopy (SEM) confirmed that the mechanism of action involves pore formation, hyphal disruption and induction of reactive oxygen species in Candida cell membrane. The antifungal spectrum was extended to A. flavus, a known ocular pathogen, where combination therapy using sub-inhibitory concentrations of Epinecidin-1 and its variant peptides with Amphotericin B and Miconazole showed enhanced synergistic effects, reducing required dosages for effective pathogen control.