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51.
Valter Bergant Shintaro Yamada Vincent Grass Yuta Tsukamoto Teresa Lavacca Karsten Krey MariaTeresa Mühlhofer Sabine Wittmann Armin Ensser Alexandra Herrmann Anja vom Hemdt Yuriko Tomita Shutoku Matsuyama Takatsugu Hirokawa Yiqi Huang Antonio Piras Constanze A Jakwerth Madlen Oelsner Susanne Thieme Alexander Graf Stefan Krebs Helmut Blum Beate M Kümmerer Alexey Stukalov Carsten B SchmidtWeber Manabu Igarashi Thomas Gramberg Andreas Pichlmair Hiroki Kato 《The EMBO journal》2022,41(17)
The SARS‐CoV‐2 infection cycle is a multistage process that relies on functional interactions between the host and the pathogen. Here, we repurposed antiviral drugs against both viral and host enzymes to pharmaceutically block methylation of the viral RNA 2''‐O‐ribose cap needed for viral immune escape. We find that the host cap 2''‐O‐ribose methyltransferase MTr1 can compensate for loss of viral NSP16 methyltransferase in facilitating virus replication. Concomitant inhibition of MTr1 and NSP16 efficiently suppresses SARS‐CoV‐2 replication. Using in silico target‐based drug screening, we identify a bispecific MTr1/NSP16 inhibitor with anti‐SARS‐CoV‐2 activity in vitro and in vivo but with unfavorable side effects. We further show antiviral activity of inhibitors that target independent stages of the host SAM cycle providing the methyltransferase co‐substrate. In particular, the adenosylhomocysteinase (AHCY) inhibitor DZNep is antiviral in in vitro, in ex vivo, and in a mouse infection model and synergizes with existing COVID‐19 treatments. Moreover, DZNep exhibits a strong immunomodulatory effect curbing infection‐induced hyperinflammation and reduces lung fibrosis markers ex vivo. Thus, multispecific and metabolic MTase inhibitors constitute yet unexplored treatment options against COVID‐19. 相似文献
52.
Roberto Menzel Samuel Dorey Tanja Maier Ina Pahl Armin Hauk 《Biotechnology progress》2022,38(1):e3214
The biopharmaceutical industry gains enormous flexibility in production processes by using sterilized preassembled single-use devices. Gamma irradiation is an established sterilization technology that may be restricted in the future by the availability of 60Co as irradiation source and irradiation capacities. X-ray technology is considered an alternative type of radiation for sterilizing SU equipment. In the context of extractables and leachables—one concern connected with the use of single-use process equipment—the effect of X-ray irradiation on the extractables profile of the materials needs to be compared to established gamma irradiation to qualify this alternative technology. An approach is presented to obtain robust and comprehensive extractables data for materials used in SU devices after sterilization either using X-ray or gamma irradiation. A careful selection of the test items and the test design allows a one-to-one comparison of data obtained from a combination of orthogonal analytical techniques. The extractables of a modern SU film material and the copolyester Tritan™ are evaluated. The data presented allow a risk evaluation on the safety of this new sterilization modality for biopharmaceutical applications. It is demonstrated that the extractables profile of a polymer is not affected by the type of irradiation used for sterilization. 相似文献
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The ultrastructure of dikaryotic haustoria of sevenPucciniastrum species,Thekopsora galii, Naohidemyces vaccinii, andCalyptospora goeppertiana was investigated.Pucciniastrum actinidiae, P. agrimoniae, P. pyrolae, andCalyptospora goeppertiana revealed haustoria whose necks were wrapped by a fold of the extrahaustorial matrix. The matrix-fold ofCalyptospora goeppertiana was characteristically shaped.Pucciniastrum circaeae, P. epilobii, P. hikosanense, P. styracinum, Thekopsora galii, andNaohidemyces vaccinii showed typical haustorial necks which were not sheathed by a matrix-fold. Haustorial necks which were wrapped by a fold of the extrahaustorial matrix were designated velopedunculate, and those which were naked gymnopedunculate. The application of haustorial ultrastructure as a character for use in systematics is discussed.Part 112 of the series Studies in Heterobasidiomycetes. 相似文献
55.
Binding of ovarian cancer antigen CA125/MUC16 to mesothelin mediates cell adhesion 总被引:14,自引:0,他引:14
Rump A Morikawa Y Tanaka M Minami S Umesaki N Takeuchi M Miyajima A 《The Journal of biological chemistry》2004,279(10):9190-9198
Mesothelin is a glycosylphosphatidylinositol-linked cell surface molecule expressed in the mesothelial lining of the body cavities and in many tumor cells. Based on the finding that a soluble form of mesothelin specifically binds to ovarian carcinoma cell line OVCAR-3, we isolated cDNAs encoding a mesothelin-binding protein by expression cloning. The polypeptides encoded by the two cloned cDNA fragments matched to portions of CA125, an ovarian cancer antigen and a giant mucin-like glycoprotein present at the surface of tumor cells. By flow cytometric analysis and immunoprecipitation, we demonstrate that CA125 binds to mesothelin in a specific manner. Binding of CA125 to membrane-bound mesothelin mediates heterotypic cell adhesion as anti-mesothelin antibody blocks binding of OVCAR-3 cells expressing CA125 to an endothelial-like cell line expressing mesothelin. Finally, we show that CA125 and mesothelin are co-expressed in advanced grade ovarian adenocarcinoma. Taken together, our data indicate that mesothelin is a novel CA125-binding protein and that CA125 might contribute to the metastasis of ovarian cancer to the peritoneum by initiating cell attachment to the mesothelial epithelium via binding to mesothelin. 相似文献
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An isolate (G15) of a bacterium, frequently isolated from roots of various plant species, was identified asSerratia plymuthica. At low temperature (viz. 2–8°C), the studied isolated readily produced a red pigment which proved useful in recognizing the bacteria on reisolation.
In laboratory tests it exhibited strong antagonism againstBotrytis cinerea andGerlachia nivalis and moderate antagonism againstRhizoctonia solani, Fusarium culmorum andPythium sp. The bacterium significantly increased growth of lettuce plants when applied to the roots under non-sterile conditions
in greenhouse tests. Various strains ofSerratia plymuthica are supposed to be common as rhizosphere bacteria under Swedish conditions. 相似文献
58.
Kinetics of Hyal-1 and PH-20 hyaluronidases: comparison of minimal substrates and analysis of the transglycosylation reaction 总被引:2,自引:0,他引:2
The availability of recombinant expression systems for the production of purified human hyaluronidases PH-20 and Hyal-1 facilitated the first detailed analysis of the enzymatic reaction products. The human recombinant enzymes, both expressed by Drosophila Schneider-2 (DS-2) cells, were compared to bovine testicular hyaluronidase (BTH), a commercially available hyaluronidase preparation, which has long been considered a prototype of mammalian hyaluronidases. The conversion of low molecular weight hyaluronic acid (HA) fragments was detected by a capillary zone electrophoresis (CZE) method. Surprisingly, the HA hexasaccharide, which is generally accepted to be the minimum substrate of BTH, was not a substrate of recombinant human PH-20 and Hyal-1. However, HA octasaccharide was converted efficiently by both enzymes, thus representing the minimum substrate for human PH-20 and Hyal-1. Additionally, BTH was shown to catabolize the HA hexasaccharide at pH 4.0 mainly by hydrolysis, while at pH 6.0 transglycosylation prevailed. Human PH-20 was found to catalyze both hydrolysis and transglycosylation of the HA octasaccharide. On the contrary, human Hyal-1 converted the HA octasaccharide mainly by hydrolysis with transglycosylation products occurring only at high substrate concentrations (> or = 500 microM). The differences between the hyaluronidase subtypes and isoenzymes were much more prominent than expected. Obviously, the different hyaluronidase subtypes have evolved into very specialized enzymes with respect to their catalytic mechanism of action. 相似文献
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60.
Allometric plasticity in a polyphenic beetle 总被引:1,自引:0,他引:1
Armin P. Moczek 《Ecological Entomology》2002,27(1):58-67
Abstract 1. Environmental conditions, such as variation in nutrition, commonly contribute to morphological variation among individuals by affecting body size and the expression of certain morphological traits; however the scaling relationship between a morphological trait and body size over a range of body sizes is generally assumed not to change in response to environmental fluctuation (allometric plasticity), but instead to be constant and diagnostic for a particular trait and species or population. The work reported here examined diet‐induced allometric plasticity in the polyphenic beetle Onthophagus taurus Schreber (1759) (Coleoptera: Scarabaeidae). 2. Male O. taurus vary in body size depending on larval nutrition. Only males above a critical body size threshold express fully developed horns; males smaller than this threshold develop only rudimentary horns or no horns at all. 3. Field populations that naturally utilise two different resources for feeding larvae (horse dung vs. cow manure) exhibited significant differences in the average scaling relationship between body size and male horn length over the same range of body sizes. Males collected from cow manure populations expressed consistently longer horns for a given body size than males collected from horse dung populations. 4. Males reared in the laboratory on horse dung or cow manure also exhibited significant differences in the average scaling relationship between body size and horn length. Differences between laboratory populations reared on horse dung or cow manure were of the same kind and magnitude as differences between field populations that utilise these different resources naturally. 5. These findings suggest that between‐population differences in scaling relationships between horn length and body size can be the product of differences in the quality of resources available to developing larvae. Results are discussed in the context of onthophagine mating systems and recent insights in the developmental and endocrine control of horn polyphenisms. 相似文献