The aims of the laboratory founded in 2005 are structural studies of membrane and soluble biological macromolecular complexes using methods of X-ray diffraction. X-ray crystallography is the major technique to get the structure of biological macromolecules at atomic resolution. These protein structures are central to understand the detailed mechanisms of biological processes and to discover novel therapeutics using a structure-based approach. Almost weekly, known scientific journals as Science, Nature or Cell feature striking drawings of large biological molecular assemblies and appropriate articles describe the role and function in their biological environments. To counter the myriad existent threats of diseases and terrorism, there is an urgent need to interpret the relevance of macromolecular structures published nowadays. We have crystallized several non-membrane (e.g. flavodoxin-like protein WrbA of E.coli, cytochromes of photosynthetic bacteria Thiocapsa roseopersicina, HsdR subunit of the type IB restriction enzyme EcoR124I, several haloalkane dehalogenases mutants) and two membrane protein complexes (monomeric and dimeric core complex of photosystem II from higher plants, and PSI and PSII protein complexes from thermophilic red algae), which are important for living on the earth. These protein complexes are crystallized using standard and advanced crystallization techniques. Obtained monocrystals have been measured at the synchrotron radiation sources and diffraction data have been used to solve a protein structure.