Lectins are proteins or glycoproteins of non-immune origin which recognize and bind reversibly to diverse sugar structures. They are involved in recognition events in a variety of physiological and pathological processes. One of the most interesting biological function of these sugar-specific proteins is their involvement in host-pathogen interactions. Wide range of pathogenic bacteria and viruses use their surface lectins (called adhesins) for recognition and adhesion to host tissues – in the the crucial step for initiation of infection. Inhibition of these lectins by suitable carbohydrates or their analogs might prevent attachment of pathogens to host cells and prevent the disease outbreak. Aspergillus fumigatus is an ubiquitous saprophytic mold and opportunistic pathogen responsible for severe infections in immuno-compromised individuals. The project is focused on a detailed characterization of L-fucose specific lectin AFL from A. fumigatus.