The research team has been engaged in several topics. The principal field is represented by mass spectrometry in protein analysis. There are instruments available for the separation of proteins and peptides completed by mass spectrometers with MALDI and ESI ionization. Common methods for the preparation and purification of samples are used. Routine identifications of proteins are performed (peptide mass fingerprinting and peptide sequencing) together with relative and absolute quantification and analysis of posttranslational modifications (glycosylation, phosphorylation). The scope of the research work is broad: from analysis of a single protein of choice to charting proteomes. Mass spectrometry of intact cells and spores is utilized for the identification of microorganisms. In addition, there are also enzymes studied, namely those of a plant or microbial origin, such as dehydrogenases, oxidases and proteases. The enzymes are obtained by isolation from their natural sources (tissues or cells) or by recombinant expression of the corresponding genes in host microorganisms. Their study involves description of molecular properties, determination of typical substrates and inhibitors and, in some cases, crystallization and structural analysis. Moreover, ways are sought to a practical application of enzymes in food analysis. For that purpose, either biosensors are constructed or the enzymes are immobilized on solid supports. Finally, investigations on metabolic pathways for the biosynthesis and biodegradation of certain metabolites (e.g. plant hormones) are worth of mentioning.