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91.
Jean Ballongue Eberhard Masion Jamal Amine Henri Petitdemange Robert Gay 《Applied microbiology and biotechnology》1987,26(6):568-573
Summary The growth of Clostridium acetobutylicum was studied by three ways. 1. In batch fermentation, referred to as the control. 2. Fermentation in dialysis which permits
elimination of all the products of metabolism: acids, solvents and gases. In order to test the toxic effect of acids, cultures
were dialysed against 2 g l-1 acetic acid or 2 g l-1 butyric acid. 3. To test the toxic effect of gases only, batch fermentations were carried out under vacuum or with a continuous
bubbling of nitrogen.
The first method resulted in a productivity of 1.2 g l-1 dry cell weight and a maximal specific growth rate of 0.2 h-1; the second, 20 g l-1 dry cell weight and a constant maximum specific growth rate (μ=0.39 h-1) between 14 and 20 h. The toxic effect of acetic and butyric acids, starts at low concentrations and about 4 g l-1 of both acids results in a decrease of 50% of maximal specific growth rate. The third series of experiments showed that gases
produced by the bacteria have a high toxic effect, comparable to that of 5 g l-1 of acid. 相似文献
92.
93.
Andrea Paolella Wen Zhu Gui‐Liang Xu Andrea La Monaca Sylvio Savoie Gabriel Girard Ashok Vijh Hendrix Demers Alexis Perea Nicolas Delaporte Abdelbast Guerfi Xiang Liu Yang Ren Cheng‐Jun Sun Jun Lu Khalil Amine Karim Zaghib 《Liver Transplantation》2020,10(32)
The thickness of solid‐state electrolytes (SSEs) significantly affects the energy density and safety performance of all‐solid‐state lithium batteries. However, a sufficient understanding of the reactivity toward lithium metal of ultrathin SSEs (<100 µm) based on NASICON remains lacking. Herein, for the first time, a self‐standing and ultrathin (70 µm) NASICON‐type Li1.5Al0.5Ge1.5(PO4)3 (LAGP) electrolyte via a scalable solution process is developed, and X‐ray photoelectron spectroscopy reveals that changes in LAGP at the metastable Li–LAGP interface during battery operation is temperature dependent. Severe germanium reduction and decrease in LAGP particle size are detected at the Li–LAGP interface at elevated temperature. Oriented plating of lithium metal on its preferred (110) face occurs during in situ X‐ray diffraction cycling. 相似文献
94.
Koufan Meriyem Belkoura Ilham Mazri Mouaad Amine Amarraque Abderrahim Essatte Amine Elhorri Hafsa Zaddoug Fatima Alaoui Tajlmolk 《Plant Cell, Tissue and Organ Culture》2020,141(1):217-227
Plant Cell, Tissue and Organ Culture (PCTOC) - Argan (Argania spinosa (L.) Skeels) is an endangered and endemic agroforestry species of Morocco highly appreciated for its nutraceutical properties.... 相似文献
95.
Koufan Meriyem Mazri Mouaad Amine Essatte Amine Moussafir Sanae Belkoura Ilham El Rhaffari Lhoussaine Toufik Ibrahim 《Plant Cell, Tissue and Organ Culture》2020,140(2):369-378
Plant Cell, Tissue and Organ Culture (PCTOC) - European mistletoe (Viscum album) is a medicinal plant with significant anticancer properties. In vitro callus production provides an essential... 相似文献
96.
97.
Lorena Infante Lara Alexis Sledge Amine Laradji Cosmas O. Okoro Neil Osheroff 《Bioorganic & medicinal chemistry letters》2017,27(3):586-589
A number of topoisomerase II-targeted anticancer drugs, including amsacrine, utilize an acridine or related aromatic core as a scaffold. Therefore, to further explore the potential of acridine-related compounds to act as topoisomerase II poisons, we synthesized a series of novel trifluoromethylated 9-amino-3,4-dihydroacridin-1(2H)-one derivatives and examined their ability to enhance DNA cleavage mediated by human topoisomerase IIα. Derivatives containing a H, Cl, F, and Br at C7 enhanced enzyme-mediated double-stranded DNA cleavage ~5.5- to 8.5-fold over baseline, but were less potent than amsacrine. The inclusion of an amino group at C9 was critical for activity. The compounds lost their activity against topoisomerase IIα in the presence of a reducing agent, displayed no activity against the catalytic core of topoisomerase IIα, and inhibited DNA cleavage when incubated with the enzyme prior to the addition of DNA. These findings strongly suggest that the compounds act as covalent, rather than interfacial, topoisomerase II poisons. 相似文献
98.
Fang X Ye L Timani KA Li S Zen Y Zhao M Zheng H Wu Z 《Journal of biochemistry and molecular biology》2005,38(4):381-385
Severe acute respiratory syndrome (SARS) is an emerging infectious disease associated with a novel coronavirus (CoV) that was identified and molecularly characterized in 2003. Previous studies on various coronaviruses indicate that protein-protein interactions amongst various coronavirus proteins are critical for viral assembly and morphogenesis. It is necessary to elucidate the molecular mechanism of SARS-CoV replication and rationalize the anti-SARS therapeutic intervention. In this study, we employed an in vitro GST pull-down assay to investigate the interaction between the membrane (M) and the nucleocapsid (N) proteins. Our results show that the interaction between the M and N proteins does take place in vitro. Moreover, we provide an evidence that 12 amino acids domain (194-205) in the M protein is responsible for binding to N protein. Our work will help shed light on the molecular mechanism of the virus assembly and provide valuable information pertaining to rationalization of future anti-viral strategies. 相似文献
99.
Three recent reports (Baoxiu Qi et al., Amine Abbadi et al. and Anthony J. Kinney et al.) describe the production of very long-chain polyunsaturated fatty acids in transgenic plants. This might lead to a sustainable source of these valuable fatty acids for use in human food and animal feed. At present they are mainly available via consumption of fish, which is a limited and endangered resource. 相似文献
100.
Insights into human Lck SH3 domain binding specificity: different binding modes of artificial and native ligands 总被引:1,自引:0,他引:1
Tran T Hoffmann S Wiesehan K Jonas E Luge C Aladag A Willbold D 《Biochemistry》2005,44(45):15042-15052
We analyzed the ligand binding specificity of the lymphocyte specific kinase (Lck) SH3 domain. We identified artificial Lck SH3 ligands using phage display. In addition, we analyzed Lck SH3 binding sites within known natural Lck SH3 binding proteins using an Lck specific binding assay on membrane-immobilized synthetic peptides. On one hand, from the phage-selected peptides, representing mostly special class I' ligands, a well-defined consensus sequence was obtained. Interestingly, a histidine outside the central polyproline motif contributes significantly to Lck SH3 binding affinity and specificity. On the other hand, we confirmed previously mapped Lck SH3 binding sites in ADAM15, HS1, SLP76, and NS5A, and identified putative Lck SH3 binding sites of Sam68, FasL, c-Cbl, and Cbl-b. Without exception, the comparatively diverse Lck SH3 binding sites of all analyzed natural Lck SH3 binding proteins emerged as class II proteins. Possible explanations for the observed variations between artificial and native ligands-which are not due to significant K(D) value differences as shown by calculating Lck SH3 affinities of artificial peptide PD1-Y(-3)R as well as for peptides comprising putative Lck SH3 binding sites of NS5A, Sos, and Sam68-are discussed. Our data suggest that phage display, a popular tool for determining SH3 binding specificity, must-at least in the case of Lck-not irrevocably mirror physiologically relevant protein-ligand interactions. 相似文献