Lectins are ubiquitous proteins and glycoproteins with the ability to specifically, non-covalently and reversibly bind to the mono-, oligo- and polysaccharides. These sugar-binding proteins can be found in most organisms, ranging from viruses and bacteria to plants and animals. They play an important role in many processes occurring in nature such as cell-cell interaction or recognition of the host by a pathogen. Lectins represent a heterogeneous group of proteins that vary in size, oligomeric state, structure as well as in exhibit specificity. Due to their importance, lectins are studied structurally and functionally to completely understand their role and mechanism of action. Our research focuses on the lectins from gram-negative entomopathogenic bacteria Photorhabdus asymbiotica, which live in symbiosis with Heterorhabditis nematodes. This symbiotic complex can be found in soil, where it searches for the insect prey. Even though the Photorhabdus genus is mainly insect pathogen there are also clinical cases describing a human infection caused by this bacterium. P. asymbiotica produces the well-characterized lectin PHL which has a seven-bladed beta-propeller fold and contains two types of binding sites for different ligands. In addition, bioinformatic analysis of the P. asymbiotica genome revealed a presence of two additional genes for homologous proteins with the PHL lectin. Several sugar-binding proteins with unknown function and dual behaviour makes P. asymbiotica a compelling organism and further studies of biomolecules produced by this bacterium may reveal their importance in the pathogenic or a symbiotic stage of life.