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951.
Syncytial muscles arise by the fusion of mononucleated myoblasts. Main cellular events during the fusion of mammalian and Drosophila myoblasts are the recognition and adhesion of myoblasts, F‐actin polymerization, formation of the fusion pore, blending of the cytoplasm and the integration of the fusing myoblast into the growing myotube. During the last twenty years many key players of myoblast fusion have been identified in the model organism Drosophila melanogaster. However, none of these proteins showed fusogenic characteristics. During the last five years, two new proteins have been identified in mice that control membrane remodeling and that possess fusogenic properties. These proteins might in the future help to increase our knowledge about the fundamental mechanism of myoblast fusion. 相似文献
952.
Nicola Gasparini Simon Kahmann Michael Salvador Jose Dario Perea Andreas Sperlich Andreas Baumann Ning Li Stefanie Rechberger Erdmann Spiecker Vladimir Dyakonov Giuseppe Portale Maria A. Loi Christoph J. Brabec Tayebeh Ameri 《Liver Transplantation》2019,9(19)
Ternary blends with broad spectral absorption have the potential to increase charge generation in organic solar cells but feature additional complexity due to limited intermixing and electronic mismatch. Here, a model system comprising the polymers poly[5,5‐bis(2‐butyloctyl)‐(2,2‐bithiophene)‐4,4‐dicarboxylate‐alt‐5,5‐2,2‐bithiophene] (PDCBT) and PTB7‐Th and PC70BM as an electron accepting unit is presented. The power conversion efficiency (PCE) of the ternary system clearly surpasses the performance of either of the binary systems. The photophysics is governed by a fast energy transfer process from PDCBT to PTB7‐Th, followed by electron transfer at the PTB7‐Th:fullerene interface. The morphological motif in the ternary blend is characterized by polymer fibers. Based on a combination of photophysical analysis, GIWAXS measurements and calculation of the intermolecular parameter, the latter indicating a very favorable molecular affinity between PDCBT and PTB7‐Th, it is proposed that an efficient charge generation mechanism is possible because PTB7‐Th predominantly orients around PDCBT filaments, allowing energy to be effectively relayed from PDCBT to PTB7‐Th. Fullerene can be replaced by a nonfullerene acceptor without sacrifices in charge generation, achieving a PCE above 11%. These results support the idea that thermodynamic mixing and energetics of the polymer–polymer interface are critical design parameter for realizing highly efficient ternary solar cells with variable electron acceptors. 相似文献
953.
Stefanie Arnold Karin Moss Nicolaus Dahmen Marius Henkel Rudolf Hausmann 《Global Change Biology Bioenergy》2019,11(1):181-190
This work evaluates a biorefinery approach for microbial valorization of bio‐oil fractions produced by fast pyrolysis of ash‐rich lignocellulosic biomass. Different methods are presented for the pretreatment of the low‐sugar complex bio‐oil consisting of organic condensate (OC) and aqueous condensate (AC) to overcome their strong inhibitory effects and unsuitability for common analytical methods. Growth of Pseudomonas putida KT2440, which was chosen as a reference system, on untreated bio‐oil fractions was only detectable using solid medium with OC as sole carbon source. Utilization of a pretreated OC which was filtered, autoclaved, neutralized and centrifuged enabled growth in liquid medium with significant remaining optical instability. By subjecting the pretreated fractions to solid phase extraction, more stable and less inhibitory bio‐oil fractions could be obtained enabling the appliance of common analytical methods. Furthermore, this pretreatment facilitated growth of the applied reference organism Pseudomonas putida KT2440. As there is currently no convincing strategy for reliable application of bio‐oil as a sole source of carbon in industrial biotechnology, the presented work depicts a first step toward establishing bio‐oil as a future sustainable feedstock for a bio‐based economy. 相似文献
954.
Sophie Dietz Katharina Herz Stefanie Dll Sylvia Haider Ute Jandt Helge Bruelheide Dierk Scheel 《Ecology and evolution》2019,9(10):5526-5541
In the rhizosphere, plants are exposed to a multitude of different biotic and abiotic factors, to which they respond by exuding a wide range of secondary root metabolites. So far, it has been unknown to which degree root exudate composition is species‐specific and is affected by land use, the local impact and local neighborhood under field conditions. In this study, root exudates of 10 common grassland species were analyzed, each five of forbs and grasses, in the German Biodiversity Exploratories using a combined phytometer and untargeted liquid chromatography‐mass spectrometry (LC‐MS) approach. Redundancy analysis and hierarchical clustering revealed a large set of semi‐polar metabolites common to all species in addition to species‐specific metabolites. Chemical richness and exudate composition revealed that forbs, such as Plantago lanceolata and Galium species, exuded more species‐specific metabolites than grasses. Grasses instead were primarily affected by environmental conditions. In both forbs and grasses, plant functional traits had only a minor impact on plant root exudation patterns. Overall, our results demonstrate the feasibility of obtaining and untargeted profiling of semi‐polar metabolites under field condition and allow a deeper view in the exudation of plants in a natural grassland community. 相似文献
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Stefanie Hagen Friedel Drepper Sven Fischer Krisztian Fodor Daniel Passon Harald W. Platta Michael Zenn Wolfgang Schliebs Wolfgang Girzalsky Matthias Wilmanns Bettina Warscheid Ralf Erdmann 《The Journal of biological chemistry》2015,290(44):26610-26626
The peroxisomal matrix protein import is facilitated by cycling import receptors that shuttle between the cytosol and the peroxisomal membrane. The import receptor Pex5p mediates the import of proteins harboring a peroxisomal targeting signal of type I (PTS1). Purified recombinant Pex5p forms a dimeric complex with the PTS1-protein Pcs60p in vitro with a KD of 0.19 μm. To analyze the structural basis for receptor-cargo recognition, the PTS1 and adjacent amino acids of Pcs60p were systematically scanned for Pex5p binding by an in vitro site-directed photo-cross-linking approach. The cross-linked binding regions of the receptor were subsequently identified by high resolution mass spectrometry. Most cross-links were found with TPR6, TPR7, as well as the 7C-loop of Pex5p. Surface plasmon resonance analysis revealed a bivalent interaction mode for Pex5p and Pcs60p. Interestingly, Pcs60p lacking its C-terminal tripeptide sequence was efficiently cross-linked to the same regions of Pex5p. The KD value of the interaction of truncated Pcs60p and Pex5p was in the range of 7.7 μm. Isothermal titration calorimetry and surface plasmon resonance measurements revealed a monovalent binding mode for the interaction of Pex5p and Pcs60p lacking the PTS1. Our data indicate that Pcs60p contains a second contact site for its receptor Pex5p, beyond the C-terminal tripeptide. The physiological relevance of the ancillary binding region was supported by in vivo import studies. The bivalent binding mode might be explained by a two-step concept as follows: first, cargo recognition and initial tethering by the PTS1-receptor Pex5p; second, lock-in of receptor and cargo. 相似文献
959.
Laura K. Pritchard Daniel I. R. Spencer Louise Royle Snezana Vasiljevic Stefanie A. Krumm Katie J. Doores Max Crispin 《Journal of virology》2015,89(13):6952-6959
Broadly neutralizing antibodies have been isolated that bind the glycan shield of the HIV-1 envelope spike. One such antibody, PGT135, contacts the intrinsic mannose patch of gp120 at the Asn332, Asn392, and Asn386 glycosylation sites. Here, site-specific glycosylation analysis of recombinant gp120 revealed glycan microheterogeneity sufficient to explain the existence of a minor population of virions resistant to PGT135 neutralization. Target microheterogeneity and antibody glycan specificity are therefore important parameters in HIV-1 vaccine design. 相似文献
960.