Lectin that specifically binds to L-fucose and weakly reacts with mannose and N-acetyl-neuraminic acid (PubMed:12092808, PubMed:27318092, PubMed:28041800). Has strongest preference for the alpha-1,6-fucosylated chain (core fucose) on glycoproteins among alpha-1,2-, alpha-1,3-, alpha-1,4-, and alpha-1,6-fucosylated chains (PubMed:17383961, PubMed:19109923). Binds to fucose residues of IgE in mice and human, causing antigen-independent IgE-mediated mast cell activation and anaphylactoid reactions in mice and is possibly implicated in allergic response to Aspergillus oryzae in humans (PubMed:21790704). Induces secretion of pro-inflammatory cytokines IL6 and IL8 implicated in ocular diseases such as mycotic keratitis, probably through its interaction with host toll-like receptors TLR2 and TLR4, followed by up-regulation of pro-inflammatory cytokines (PubMed:28470344). Homodimer (PubMed:17383961). AOL adopts the six-bladed beta-propeller fold and contains 6 binding sites per monomer, each located between two adjacent blades (PubMed:27318092, PubMed:28041800). The 6 binding sites that are non-equivalent, and owing to minor differences in amino-acid composition they exhibit a marked difference in specific ligand recognition (PubMed:27318092, PubMed:28041800). Lectins have particular value as specific probes for investigating the distribution, structure and biological function of carbohydrate chains on the cell surface of animal, plant, and microorganism because of their specificity for defined carbohydrate structures (PubMed:17383961). FleA is suitable for detecting core fucose on cell surface glycoproteins and/or a useful vehicle for delivery of substances to the inside of cells (PubMed:17383961, PubMed:21892597). Belongs to the fungal fucose-specific lectin family.