@phdthesis{GonzalezdelaCruz2019, author = {Gonzalez de la Cruz, Jorge}, title = {Metabolic engineering of Saccharomyces cerevisiae for formatotrophic growth}, school = {Universit{\"a}t Potsdam}, pages = {96}, year = {2019}, language = {en} } @phdthesis{Neukranz2019, author = {Neukranz, Yannika}, title = {MOCS3 and its role in molybdenum cofactor biosynthesis, tRNA thiolation and other cellular pathways in humans}, school = {Universit{\"a}t Potsdam}, pages = {135}, year = {2019}, language = {en} } @phdthesis{Gaballa2019, author = {Gaballa, Mohamed Mahmoud Salem Ahmed}, title = {New pharmacological approaches targeting vascular calcification in chronic kidney disease}, address = {Potsdam}, school = {Universit{\"a}t Potsdam}, pages = {X, 110}, year = {2019}, language = {en} } @phdthesis{Eichelmann2019, author = {Eichelmann, Fabian}, title = {Novel adipokines as inflammatory biomarkers of chronic disease risk}, school = {Universit{\"a}t Potsdam}, pages = {133}, year = {2019}, language = {en} } @phdthesis{Baleka2019, author = {Baleka, Sina Isabelle}, title = {Palaeogenetic analyses of extinct Elephantidae from temperate and subtropical climates}, school = {Universit{\"a}t Potsdam}, pages = {xiii, 114}, year = {2019}, language = {en} } @phdthesis{Kuecuekgoeze2019, author = {K{\"u}{\c{c}}{\"u}kg{\"o}ze, G{\"o}khan}, title = {Purification and characterization of mouse aldehyde oxidases}, school = {Universit{\"a}t Potsdam}, pages = {xiv, 125}, year = {2019}, abstract = {Mouse aldehyde oxidases (mAOXs) have a homodimeric structure and belong to xanthine oxidase family of molybdo-flavoenzymes. In general, each dimer is characterized by three subdomains: a 20 kDa N-terminal 2x[2Fe2S] cluster containing domain, a 40 kDa central FAD-containing domain and an 85 kDa C-terminal molybdenum cofactor (Moco) containing domain. Aldehyde oxidases have a broad substrate specificity including the oxidation of different aldehydes and N-heterocyclic compounds. AOX enzymes are present in mainly all eukaryotes. Four different homologs of AOX were identified to be present with varying numbers among species and rodents like mice and rats contain the highest number of AOX isoenzymes. There are four identified homologs in mouse named mAOX1, mAOX3, mAOX2, and mAOX4. The AOX homologs in mice are expressed in a tissue-specific manner. Expression of mAOX1 and mAOX3 are almost superimposable and predominantly synthesized in liver, lung, and testis. The richest source of mAOX4 is the Harderian gland, which is found within the eye's orbit in tetrapods. Expression of mAOX2 is strictly restricted to the Bowman's gland, the main secretory organ of the nasal mucosa. In this study, the four catalytically active mAOX enzymes were expressed in a heterologous expression system in Escherichia coli and purified in a catalytically active form. Thirty different structurally related aromatic, aliphatic and N-heterocyclic compounds were used as substrates, and the kinetic parameters of all four mAOX enzymes were directly compared. The results showed that all enzymes can catalyze a broad range of substrates. Generally, no major differences between mAOX1, mAOX3 and mAOX2 were identified and the substrate specificity of mAOX1, mAOX3, and mAOX2 was broader compared to that of mAOX4 since mAOX4 showed no activity with substrates like methoxy-benzaldehydes, phenanthridine, N1-methyl-nicotinamide, and cinnamaldehyde and 4-(dimethylamino)cinnamaldehyde. We investigated differences at the flavin site of the mAOX enzymes by measuring the ability of the four mAOX enzymes to oxidize NADH in the absence of oxygen. NADH was able to reduce only mAOX3. The four mouse AOXs are also characterized by quantitative differences in their ability to produce superoxide radicals. mAOX2 is the enzyme generating the largest rate of superoxide radicals of around 40\% in relation to moles of substrate converted and it is followed by mAOX1 with a ratio of 30\%. To understand the factors that contribute to the substrate specificity of mAOX4, site-directed mutagenesis was applied to substitute amino acids in the substrate-binding funnel by the ones present in mAOX1, mAOX3, and mAOX2. The amino acids Val1016, Ile1018 and Met1088 were selected as targets. An increase in activity was obtained by the amino acid exchange M1088V in the active site identified to be specific for mAOX4, to the amino acid identified in mAOX3.}, language = {en} } @phdthesis{Schumacher2019, author = {Schumacher, Julia}, title = {Regulation and function of STERILE APETALA in Arabidopsis flower development}, school = {Universit{\"a}t Potsdam}, pages = {144}, year = {2019}, abstract = {STERILE APETALA (SAP) is known to be an essential regulator of flower development for over 20 years. Loss of SAP function in the model plant Arabidopsis thaliana is associated with a reduction of floral organ number, size and fertility. In accordance with the function of SAP during early flower development, its spatial expression in flowers is confined to meristematic stages and to developing ovules. However, to date, despite extensive research, the molecular function of SAP and the regulation of its spatio-temporal expression still remain elusive. In this work, amino acid sequence analysis and homology modeling revealed that SAP belongs to the rare class of plant F-box proteins with C-terminal WD40 repeats. In opisthokonts, this type of F-box proteins constitutes the substrate binding subunit of SCF complexes, which catalyze the ubiquitination of proteins to initiate their proteasomal degradation. With LC-MS/MS-based protein complex isolation, the interaction of SAP with major SCF complex subunits was confirmed. Additionally, candidate substrate proteins, such as the growth repressor PEAPOD 1 and 2 (PPD1/2), could be revealed during early stages of flower development. Also INDOLE-3-BUTYRIC ACID RESPONSE 5 (IBR5) was identified among putative interactors. Genetic analyses indicated that, different from substrate proteins, IBR5 is required for SAP function. Protein complex isolation together with transcriptome profiling emphasized that the SCFSAP complex integrates multiple biological processes, such as proliferative growth, vascular development, hormonal signaling and reproduction. Phenotypic analysis of sap mutant and SAP overexpressing plants positively correlated SAP function with plant growth during reproductive and vegetative development. Furthermore, to elaborate on the transcriptional regulation of SAP, publicly available ChIP-seq data of key floral homeotic proteins were reanalyzed. Here, it was shown that the MADS-domain transcription factors APETALA 1 (AP1), APETALA 3 (AP3), PISTILLATA (PI), AGAMOUS (AG) and SEPALLATA 3 (SEP3) bind to the SAP locus, which indicates that SAP is expressed in a floral organ-specific manner. Reporter gene analyses in combination with CRISPR/Cas9-mediated deletion of putative regulatory regions further demonstrated that the intron contains major regulatory elements of SAP in Arabidopsis thaliana. In conclusion, these data indicate that SAP is a pleiotropic developmental regulator that acts through tissue-specific destabilization of proteins. The presumed transcriptional regulation of SAP by the floral MADS-domain transcription factors could provide a missing link between the specification of floral organ identity and floral organ growth pathways.}, language = {en} } @phdthesis{Langhammer2019, author = {Langhammer, Maria}, title = {Simulating biodiversity responses to land use mosaics in agricultural landscapes}, school = {Universit{\"a}t Potsdam}, year = {2019}, language = {en} } @phdthesis{Schiro2019, author = {Schiro, Gabriele}, title = {Spatial distribution of phyllosphere fungi in topographically heterogeneous wheat fields}, school = {Universit{\"a}t Potsdam}, pages = {105}, year = {2019}, language = {en} } @phdthesis{Ramming2019, author = {Ramming, Anna}, title = {Specific Roles of POLY(A) POLYMERASE1 in the male Gametophyte and Beyond}, school = {Universit{\"a}t Potsdam}, pages = {143}, year = {2019}, language = {en} }