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This thesis systematically examines the degree programmes in the field of food science and technology offered by Swiss universities of applied sciences and the federal institutes of technology. Universities and universities of applied sciences educate qualified professionals for the economy, academia, and society. Due to the continuously changing needs of the labour market, those institutions have to develop their degree programmes in a constant and circular process, the curriculum value chain. This thesis proposes a method to convert the qualitative statements of the course descriptions into a quantitative and comprehensive evaluation on specific aspects of the curricula, thereby identifying the main differences in the curricula structure and content. Moreover, it relates these differences to the institutional factors shaping the examined institutions. In future research, scholars can apply this method to other educational institutions and degree programmes and provide the empirical information needed for upcoming curriculum reforms., CES Studies, 24

Biomolecular mass spectrometry has matured strongly over the past decades and has now reached a stage where it can provide deep insights into the structure and composition of large cellular assemblies. Here, we describe a three-tiered hybrid mass spectrometry approach that enables the dissection of macromolecular complexes in order to complement structural studies. To demonstrate the capabilities of the approach, we investigate ribosomes, large ribonucleoprotein particles consisting of a multitude of protein and RNA subunits. We identify sites of sequence processing, protein post-translational modifications, and the assembly and stoichiometry of individual ribosomal proteins in four distinct ribosomal particles of bacterial, plant and human origin. Amongst others, we report extensive cysteine methylation in the zinc finger domain of the human S27 protein, the heptameric stoichiometry of the chloroplastic stalk complex, the heterogeneous composition of human 40S ribosomal subunits and their association to the CrPV, and HCV internal ribosome entry site RNAs., Nature Communications, 9 (1), ISSN:2041-1723

Mitochondria and chloroplasts are cellular organelles with important functions in the energy metabolism of eukaryotic cells by hosting the protein complexes catalysing the oxidative phosphorylation and the photosynthetic reaction, respectively. They have independently evolved by the endosymbiosis of ancestral bacteria with eukaryotic progenitor cells. Essential membrane proteins of the oxidative phosphorylation and the photosynthesis machinery are still encoded on the residual organellar genomes and synthesized by the in-house translation apparatus, the mitochondrial and the chloroplast ribosome, respectively. Although sharing a common ancestor, mitoribosomes have a dramatically diverged composition and architecture in comparison to contemporary bacterial ribosomes. The high-resolution cryo-EM structures of the complete mammalian 55S mitoribosome and its 39S large and 28S small subunits presented in the first and second chapter of this thesis reveal their unique structural features and provide many important insights into the mechanism of mitochondrial protein biosynthesis. The mammalian 55S mitoribosome has a highly reduced rRNA, and the bacterial 5S rRNA is replaced by a tRNA molecule (CP tRNA) that was incorporated as a permanent part of the central protuberance. In addition, new ribosomal proteins, 28 in total, were acquired to the 55S mitoribosome providing structural stability of the reduced rRNA core and additional functionality, for example, in mRNA recruitment, intersubunit contacts, and membrane attachment. Mutations in mitoribosomal components can lead to severe human diseases that can now be understood on molecular level by inspecting the high-resolution structure of the mammalian 55S mitoribosome. In chloroplasts of plants and algae, the protein biosynthesis is coordinated with the photosynthetic activity defined by the day-night cycle and is mainly regulated at the level of translation. The high-resolution cryo-EM structure of the spinach chloroplast 70S ribosome presented in the third chapter of this thesis shows the plastid translation factor pY bound to the mRNA channel of the small subunit, where it blocks the translation initiation and stabilizes the ribosome in a non-rotated conformation during the dark phase of the day. Further, the structure reveals the plastid-specific ribosomal elements including five additional ribosomal proteins and extensions of ribosomal proteins with bacterial homologs that either play an important role in translation regulation or in structural stability. The rRNA molecules of the large subunit are fragmented to include an additional 4.5S rRNA and two strand breaks in the 23S rRNA, called hidden breaks. Taken together, the work in this thesis reveals the unique architecture of the mammalian 55S mitoribosome and the plant chloroplast 70S ribosome and provides novel insights into the mechanism of organellar protein biosynthesis and the evolution of organellar ribosomes.