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961.
Guillaume Fouché Thomas Michel Anaïs Lalève Nick X. Wang David H. Young Brigitte Meunier Danièle Debieu Sabine Fillinger Anne-Sophie Walker 《Environmental microbiology》2022,24(3):1117-1132
Acquired resistance is a threat to antifungal efficacy in medicine and agriculture. The diversity of possible resistance mechanisms and highly adaptive traits of pathogens make it difficult to predict evolutionary outcomes of treatments. We used directed evolution as an approach to assess the resistance risk to the new fungicide fenpicoxamid in the wheat pathogenic fungus Zymoseptoria tritici. Fenpicoxamid inhibits complex III of the respiratory chain at the ubiquinone reduction site (Qi site) of the mitochondrially encoded cytochrome b, a different site than the widely used strobilurins which inhibit the same complex at the ubiquinol oxidation site (Qo site). We identified the G37V change within the cytochrome b Qi site as the most likely resistance mechanism to be selected in Z. tritici. This change triggered high fenpicoxamid resistance and halved the enzymatic activity of cytochrome b, despite no significant penalty for in vitro growth. We identified negative cross-resistance between isolates harbouring G37V or G143A, a Qo site change previously selected by strobilurins. Double mutants were less resistant to both QiIs and quinone outside inhibitors compared to single mutants. This work is a proof of concept that experimental evolution can be used to predict adaptation to fungicides and provides new perspectives for the management of QiIs. 相似文献
962.
963.
Orefice Ida Di Dato Valeria Sardo Angela Lauritano Chiara Romano Giovanna 《Aquatic Ecology》2022,56(2):377-397
Aquatic Ecology - Diatoms are eukaryotic microalgae representing one of the major groups in the marine phytoplankton, accounting for up to 40% of annual productivity at sea. They are widely... 相似文献
964.
965.
Giacomo Pozzoli Hany E. Marei Asma Althani Alma Boninsegna Patrizia Casalbore Lionel N. J. L. Marlier Giulia Lanzilli Manuela Zonfrillo Giovanna Petrucci Bianca Rocca Pierluigi Navarra Alessandro Sgambato Carlo Cenciarelli 《Journal of cellular physiology》2019,234(9):15459-15471
Several clinical studies indicated that the daily use of aspirin or acetylsalicylic acid reduces the cancer risk via cyclooxygenases (Cox-1 and Cox-2) inhibition. In addition, aspirin-induced Cox-dependent and -independent antitumor effects have also been described. Here we report, for the first time, that aspirin treatment of human glioblastoma cancer (GBM) stem cells, a small population responsible for tumor progression and recurrence, is associated with reduced cell proliferation and motility. Aspirin did not interfere with cell viability but induced cell-cycle arrest. Exogenous prostaglandin E2 significantly increased cell proliferation but did not abrogate the aspirin-mediated growth inhibition, suggesting a Cox-independent mechanism. These effects appear to be mediated by the increase of p21 waf1 and p27 Kip1, associated with a reduction of Cyclin D1 and Rb1 protein phosphorylation, and involve the downregulation of key molecules responsible for tumor development, that is, Notch1, Sox2, Stat3, and Survivin. Our results support a possible role of aspirin as adjunctive therapy in the clinical management of GBM patients. 相似文献
966.
967.
Simon Gonzalez Florian Gallier Sabrina Kellouche Franck Carreiras Ettore Novellino Alfonso Carotenuto Gérard Chassaing Paolo Rovero Jacques Uziel Nadège Lubin-Germain 《生物化学与生物物理学报:生物膜》2019,1861(1):50-61
Over the past decades, membranotropic peptides such as positively charged cell-penetrating peptides (CPPs) or amphipathic antimicrobial peptides (AMPs) have received increasing interest in order to improve therapeutic agent cellular uptake.As far as we are concerned, we were interested in studying HCV fusion peptides as putative anchors. Two peptides, HCV6 and HCV7, were identified and conjugated to a fluorescent tag NBD and tested for their interaction with liposomes as model membranes. DSC and spectrofluorescence analyses demonstrate HCV7 propensity to insert or internalize in vesicles containing anionic lipids DMPG whereas no activity was observed with zwitterionic DMPC. This behavior could be explained by the peptide sequence containing a cationic arginine residue. On the contrary, HCV6 did not exhibit any membranotropic activity but was the only sequence able to induce liposomes' fusion or aggregation monitored by spectrofluorescence and DLS. This two peptides mild activity was related to their inefficient structuration in contact with membrane mimetics, which was demonstrated by CD and NMR experiments.Altogether, our data allowed us to identify two promising membrane-active peptides from E1 and E2 HCV viral proteins, one fusogenic (HCV6) and the other membranotropic (HCV7). The latter was also confirmed by fluorescence microscopy with CHO cells, indicating that HCV7 could cross the plasma membrane via an endocytosis process. Therefore, this study provides new evidences supporting the identification of HCV6 as the HCV fusion peptide as well as insights on a novel membranotropic peptide from the HCV-E2 viral protein. 相似文献
968.
Ghislaine Béhar Axelle Renodon-Cornière Stanimir Kambarev Petar Vukojicic Nathalie Caroff Stéphane Corvec Barbara Mouratou Frédéric Pecorari 《Biotechnology and bioengineering》2019,116(8):1844-1855
Detection and capture methods using antibodies have been developed to ensure identification of pathogens in biological samples. Though antibodies have many attractive properties, they also have limitations and there are needs to expand the panel of available affinity proteins with different properties. Affitins, that we developed from the Sul7d proteins, are a solid class of affinity proteins, which can be used as substitutes to antibodies or to complement them. We report the generation and characterization of antibacterial Affitins with high specificity for Staphylococcus aureus. For the first time, ribosome display selections were carried out using whole-living-cell and naïve combinatorial libraries, which avoid production of protein targets and immunization of animals. We showed that Affitin C5 exclusively recognizes S. aureus among dozens of strains, including clinical ones. C5 binds staphylococcal Protein A (SpA) with a K D of 108 ± 2 nM and has a high thermostability (T m = 77.0°C). Anti-S. aureus C5 binds SpA or bacteria in various detection and capture applications, including ELISA, western blot analysis, bead-fishing, and fluorescence imaging. Thus, novel anti-bacteria Affitins which are cost-effective, stable, and small can be rapidly and fully designed in vitro with high affinity and specificity for a surface-exposed marker. This class of reagents can be useful in diagnostic and biomedical applications. 相似文献
969.
970.
Scribano Vittorio Simakov Sergei K. Finocchiaro Claudio Correale Alessandra Scirè Salvatore 《Origins of life and evolution of the biosphere》2019,49(1-2):19-47
Origins of Life and Evolution of Biospheres - Pyrite and organic matter closely coexist in some hydrothermally-altered gabbroic xenoliths from the Hyblean Plateau, Sicily. The representative sample... 相似文献