@article{AdemKueteMbavengetal.2019, author = {Adem, Fozia A. and Kuete, Victor and Mbaveng, Armelle T. and Heydenreich, Matthias and Koch, Andreas and Ndakala, Albert and Irungu, Beatrice and Yenesew, Abiy and Efferth, Thomas}, title = {Cytotoxic flavonoids from two Lonchocarpus species}, series = {Natural Product Research}, volume = {33}, journal = {Natural Product Research}, number = {18}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {1478-6419}, doi = {10.1080/14786419.2018.1462179}, pages = {2609 -- 2617}, year = {2019}, abstract = {A new isoflavone, 4′-prenyloxyvigvexin A (1) and a new pterocarpan, (6aR,11aR)-3,8-dimethoxybitucarpin B (2) were isolated from the leaves of Lonchocarpus bussei and the stem bark of Lonchocarpus eriocalyx, respectively. The extract of L. bussei also gave four known isoflavones, maximaisoflavone H, 7,2′-dimethoxy-3′,4′-methylenedioxyisoflavone, 6,7,3′-trimethoxy-4′,5′-methylenedioxyisoflavone, durmillone; a chalcone, 4-hydroxylonchocarpin; a geranylated phenylpropanol, colenemol; and two known pterocarpans, (6aR,11aR)-maackiain and (6aR,11aR)-edunol. (6aR,11aR)-Edunol was also isolated from the stem bark of L. eriocalyx. The structures of the isolated compounds were elucidated by spectroscopy. The cytotoxicity of the compounds was tested by resazurin assay using drug-sensitive and multidrug-resistant cancer cell lines. Significant antiproliferative effects with IC50 values below 10 μM were observed for the isoflavones 6,7,3′-trimethoxy-4′,5′-methylenedioxyisoflavone and durmillone against leukemia CCRF-CEM cells; for the chalcone, 4-hydroxylonchocarpin and durmillone against its resistant counterpart CEM/ADR5000 cells; as well as for durmillone against the resistant breast adenocarcinoma MDA-MB231/BCRP cells and resistant gliobastoma U87MG.ΔEGFR cells.}, language = {en} } @article{AlbersUestuenWitzeletal.2019, author = {Albers, Philip and {\"U}st{\"u}n, Suayib and Witzel, Katja and Kraner, Max Erdmund and B{\"o}rnke, Frederik}, title = {A Remorin from Nicotiana benthamiana Interacts with the Pseudomonas Type-III Effector Protein HopZ1a and is Phosphorylated by the Immune-Related Kinase PBS1}, series = {Molecular Plant-Microbe Interactions}, volume = {32}, journal = {Molecular Plant-Microbe Interactions}, number = {9}, publisher = {Amer phytopathological SOC}, address = {ST Paul}, issn = {0894-0282}, doi = {10.1094/MPMI-04-19-0105-R}, pages = {1229 -- 1242}, year = {2019}, abstract = {The plasma membrane (PM) is at the interface of plant-pathogen interactions and, thus, many bacterial type-III effector (T3E) proteins target membrane-associated processes to interfere with immunity. The Pseudomonas syringae T3E HopZ1a is a host cell PM-localized effector protein that has several immunity-associated host targets but also activates effector-triggered immunity in resistant backgrounds. Although HopZ1a has been shown to interfere with early defense signaling at the PM, no dedicated PM-associated HopZ1a target protein has been identified until now. Here, we show that HopZ1a interacts with the PM-associated remorin protein NbREM4 from Nicotiana benthamiana in several independent assays. NbREM4 relocalizes to membrane nanodomains after treatment with the bacterial elicitor flg22 and transient overexpression of NbREM4 in N. benthamiana induces the expression of a subset of defense-related genes. We can further show that NbREM4 interacts with the immune-related receptor-like cytoplasmic kinase avrPphB-susceptible 1 (PBS1) and is phosphorylated by PBS1 on several residues in vitro. Thus, we conclude that NbREM4 is associated with early defense signaling at the PM. The possible relevance of the HopZ1a-NbREM4 interaction for HopZ1a virulence and avirulence functions is discussed.}, language = {en} } @article{AlkerSchwerdtleSchomburgetal.2019, author = {Alker, Wiebke and Schwerdtle, Tanja and Schomburg, Lutz and Haase, Hajo}, title = {A Zinpyr-1-based Fluorimetric Microassay for Free Zinc in Human Serum}, series = {International journal of molecular sciences}, volume = {20}, journal = {International journal of molecular sciences}, number = {16}, publisher = {MDPI}, address = {Basel}, issn = {1661-6596}, doi = {10.3390/ijms20164006}, pages = {13}, year = {2019}, abstract = {Zinc is an essential trace element, making it crucial to have a reliable biomarker for evaluating an individual's zinc status. The total serum zinc concentration, which is presently the most commonly used biomarker, is not ideal for this purpose, but a superior alternative is still missing. The free zinc concentration, which describes the fraction of zinc that is only loosely bound and easily exchangeable, has been proposed for this purpose, as it reflects the highly bioavailable part of serum zinc. This report presents a fluorescence-based method for determining the free zinc concentration in human serum samples, using the fluorescent probe Zinpyr-1. The assay has been applied on 154 commercially obtained human serum samples. Measured free zinc concentrations ranged from 0.09 to 0.42 nM with a mean of 0.22 ± 0.05 nM. It did not correlate with age or the total serum concentrations of zinc, manganese, iron or selenium. A negative correlation between the concentration of free zinc and total copper has been seen for sera from females. In addition, the free zinc concentration in sera from females (0.21 ± 0.05 nM) was significantly lower than in males (0.23 ± 0.06 nM). The assay uses a sample volume of less than 10 µL, is rapid and cost-effective and allows us to address questions regarding factors influencing the free serum zinc concentration, its connection with the body's zinc status, and its suitability as a future biomarker for an individual's zinc status.}, language = {en} } @article{AltintasTakidenUteschetal.2019, author = {Altintas, Zeynep and Takiden, Aref and Utesch, Tillmann and Mroginski, Maria A. and Schmid, Bianca and Scheller, Frieder W. and S{\"u}ssmuth, Roderich D.}, title = {Integrated approaches toward high-affinity artificial protein binders obtained via computationally simulated epitopes for protein recognition}, series = {Advanced functional materials}, volume = {29}, journal = {Advanced functional materials}, number = {15}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1616-301X}, doi = {10.1002/adfm.201807332}, pages = {11}, year = {2019}, abstract = {Widely used diagnostic tools make use of antibodies recognizing targeted molecules, but additional techniques are required in order to alleviate the disadvantages of antibodies. Herein, molecular dynamic calculations are performed for the design of high affinity artificial protein binding surfaces for the recognition of neuron specific enolase (NSE), a known cancer biomarker. Computational simulations are employed to identify particularly stabile secondary structure elements. These epitopes are used for the subsequent molecular imprinting, where surface imprinting approach is applied. The molecular imprints generated with the calculated epitopes of greater stability (Cys-Ep1) show better binding properties than those of lower stability (Cys-Ep5). The average binding strength of imprints created with stabile epitopes is found to be around twofold and fourfold higher for the NSE derived peptide and NSE protein, respectively. The recognition of NSE is investigated in a wide concentration range, where high sensitivity (limit of detection (LOD) = 0.5 ng mL(-1)) and affinity (dissociation constant (K-d) = 5.3 x 10(-11)m) are achieved using Cys-Ep1 imprints reflecting the stable structure of the template molecules. This integrated approach employing stability calculations for the identification of stabile epitopes is expected to have a major impact on the future development of high affinity protein capturing binders.}, language = {en} } @article{AndresDelgadoErnstGalardiCastillaetal.2019, author = {Andr{\´e}s-Delgado, Laura and Ernst, Alexander and Galardi-Castilla, Mar{\´i}a and Bazaga, David and Peralta, Marina and M{\"u}nch, Juliane and Gonzalez-Rosa, Juan M. and Marques, In{\^e}s and Tessadori, Federico and de la Pompa, Jos{\´e} Luis and Vermot, Julien and Mercader, Nadia}, title = {Actin dynamics and the Bmp pathway drive apical extrusion of proepicardial cells}, series = {Development : Company of Biologists}, volume = {146}, journal = {Development : Company of Biologists}, number = {13}, publisher = {The Company of Biologists Ltd}, address = {Cambridge}, issn = {0950-1991}, doi = {10.1242/dev.174961}, pages = {15}, year = {2019}, abstract = {The epicardium, the outer mesothelial layer enclosing the myocardium, plays key roles in heart development and regeneration. During embryogenesis, the epicardium arises from the proepicardium (PE), a cell cluster that appears in the dorsal pericardium (DP) close to the venous pole of the heart. Little is known about how the PE emerges from the pericardial mesothelium. Using a zebrafish model and a combination of genetic tools, pharmacological agents and quantitative in vivo imaging, we reveal that a coordinated collective movement of DP cells drives PE formation. We found that Bmp signaling and the actomyosin cytoskeleton promote constriction of the DP, which enables PE cells to extrude apically. We provide evidence that cell extrusion, which has been described in the elimination of unfit cells from epithelia and the emergence of hematopoietic stem cells, is also a mechanism for PE cells to exit an organized mesothelium and fulfil their developmental fate to form a new tissue layer, the epicardium.}, language = {en} } @article{AngeleskaNikoloski2019, author = {Angeleska, Angela and Nikoloski, Zoran}, title = {Coherent network partitions}, series = {Discrete applied mathematics}, volume = {266}, journal = {Discrete applied mathematics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0166-218X}, doi = {10.1016/j.dam.2019.02.048}, pages = {283 -- 290}, year = {2019}, abstract = {Graph clustering is widely applied in the analysis of cellular networks reconstructed from large-scale data or obtained from experimental evidence. Here we introduce a new type of graph clustering based on the concept of coherent partition. A coherent partition of a graph G is a partition of the vertices of G that yields only disconnected subgraphs in the complement of G. The coherence number of G is then the size of the smallest edge cut inducing a coherent partition. A coherent partition of G is optimal if the size of the inducing edge cut is the coherence number of G. Given a graph G, we study coherent partitions and the coherence number in connection to (bi)clique partitions and the (bi)clique cover number. We show that the problem of finding the coherence number is NP-hard, but is of polynomial time complexity for trees. We also discuss the relation between coherent partitions and prominent graph clustering quality measures.}, language = {en} } @misc{Arnold2019, author = {Arnold, Patrick}, title = {The origin of morphological integration and modularity in the Mammalian Neck}, series = {Journal of morphology}, volume = {280}, journal = {Journal of morphology}, publisher = {Wiley}, address = {Hoboken}, issn = {0362-2525}, doi = {10.1002/jmor.21003}, pages = {S13 -- S13}, year = {2019}, language = {en} } @article{AwanSchiebelBoehmetal.2019, author = {Awan, Asad Bashir and Schiebel, Juliane and Boehm, Alexander and Nitschke, Joerg and Sarwar, Yasra and Schierack, Peter and Ali, Aamir}, title = {Association of biofilm formation and cytotoxic potential with multidrug resistance in clinical isolates of pseudomonas aeruginosa}, series = {EXCLI Journal}, volume = {18}, journal = {EXCLI Journal}, publisher = {Leibniz Research Centre for Working Environment and Human Factors}, address = {Dortmund}, issn = {1611-2156}, doi = {10.17179/excli2018-1948}, pages = {79 -- 90}, year = {2019}, abstract = {Multidrug resistant (MDR) Pseudomonas aeruginosa having strong biofilm potential and virulence factors are a serious threat for hospitalized patients having compromised immunity In this study, 34 P. aeruginosa isolates of human origin (17 MDR and 17 non-MDR clinical isolates) were checked for biofilm formation potential in enriched and minimal media. The biofilms were detected using crystal violet method and a modified software package of the automated VideoScan screening method. Cytotoxic potential of the isolates was also investigated on HepG2, LoVo and T24 cell lines using automated VideoScan technology. Pulse field gel electrophoresis revealed 10 PFGE types in MDR and 8 in non-MDR isolates. Although all isolates showed biofilm formation potential, strong biofilm formation was found more in enriched media than in minimal media. Eight MDR isolates showed strong biofilm potential in both enriched and minimal media by both detection methods. Strong direct correlation between crystal violet and VideoScan methods was observed in identifying strong biofilm forming isolates. High cytotoxic effect was observed by 4 isolates in all cell lines used while 6 other isolates showed high cytotoxic effect on T24 cell line only. Strong association of multidrug resistance was found with biofilm formation as strong biofilms were observed significantly higher in MDR isolates (p-value < 0.05) than non-MDR isolates. No significant association of cytotoxic potential with multidrug resistance or biofilm formation was found (p-value > 0.05). The MDR isolates showing significant cytotoxic effects and strong biofilm formation impose a serious threat for hospitalized patients with weak immune system.}, 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} } @article{BarchewitzGuljamowMeissneretal.2019, author = {Barchewitz, Tino and Guljamow, Arthur and Meißner, Sven and Timm, Stefan and Henneberg, Manja and Baumann, Otto and Hagemann, Martin and Dittmann, Elke}, title = {Non-canonical localization of RubisCO under high-light conditions in the toxic cyanobacterium Microcystis aeruginosa PCC7806}, series = {Environmental microbiology}, volume = {21}, journal = {Environmental microbiology}, number = {12}, publisher = {Wiley}, address = {Hoboken}, issn = {1462-2912}, doi = {10.1111/1462-2920.14837}, pages = {4836 -- 4851}, year = {2019}, abstract = {The frequent production of the hepatotoxin microcystin (MC) and its impact on the lifestyle of bloom-forming cyanobacteria are poorly understood. Here, we report that MC interferes with the assembly and the subcellular localization of RubisCO, in Microcystis aeruginosa PCC7806. Immunofluorescence, electron microscopic and cellular fractionation studies revealed a pronounced heterogeneity in the subcellular localization of RubisCO. At high cell density, RubisCO particles are largely separate from carboxysomes in M. aeruginosa and relocate to the cytoplasmic membrane under high-light conditions. We hypothesize that the binding of MC to RubisCO promotes its membrane association and enables an extreme versatility of the enzyme. Steady-state levels of the RubisCO CO2 fixation product 3-phosphoglycerate are significantly higher in the MC-producing wild type. We also detected noticeable amounts of the RubisCO oxygenase reaction product secreted into the medium that may support the mutual interaction of M. aeruginosa with its heterotrophic microbial community.}, language = {en} }