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21.
Hydrolysis by horse muscle acylphosphatase of (Ca2+ + Mg2+)-ATPase phosphorylated intermediate 总被引:1,自引:0,他引:1
M Stefani G Liguri A Berti P Nassi G Ramponi 《Archives of biochemistry and biophysics》1981,208(1):37-41
Horse muscle acylphosphatase (EC 3.6.1.7) was found to hydrolyze the labeled phosphorylated intermediate of (Ca2+ + Mg2+)-ATPase from rabbit muscle. In addition, the phosphorylated peptides obtained by pepsin digestion of the labeled phosphorylated microsomes were completely hydrolyzed by acylphosphatase. These findings suggest a possible regulatory role of this enzyme in vivo on the calcium transport process by sarcoplasmic reticulum. 相似文献
22.
Giuseppe Bellucci Giancarlo Berti Maria Ferretti Franco Marioni Franca Re 《Biochemical and biophysical research communications》1981,102(3):838-844
The hydrolysis of (±)--3-bromo-1,2-epoxycyclohexane in the presence of rabbit liver microsomes was investigated, and found to yield, beside -3-bromocyclohexane--1,-2-diol, 2,3-epoxycyclohexanol. It was demonstrated that the latter compound was the only product of the enzymatic reaction, whereas the diol resulted from a non enzymatic hydration in the reaction medium. These data provide the first direct proof for a general base catalysis in the enzymatic epoxide hydration, previously hypothesized on the basis of several lines of indirect evidence, and disprove alternative mechanisms involving protonation of the oxirane oxygen. 相似文献
23.
24.
Ferruccio Berti Claudio Omini Daniela Longiave 《Prostaglandins & other lipid mediators》1977,14(2):241-249
The horse-chestnut saponin Aescin, an anti-exudative compound, induces contraction of isolated portal vein of rat and rabbit. This effect appears to be mediated by Prostaglandins of Fα type.The ability of Aescin to stimulate generation and release of Prostaglandins has been demonstrated in isolated lung of the rat. Mass-fragmentographic analysis of the lung effluent indicate that when Aescin is perfused through this organ the release of PGF2α is increased. The capability of Aescin to generate Prostaglandins is discussed in connection with its anti-exudative activity. 相似文献
25.
Emanuela Ursino Alessandra M. Albertini Giulia Fiorentino Paolo Gabrieli Viola Camilla Scoffone Angelica Pellegrini Giuliano Gasperi Alessandro Di Cosimo Giulia Barbieri 《Microbial biotechnology》2020,13(6):1972-1982
Aedes albopictus transmits several arboviral infections. In the absence of vaccines, control of mosquito populations is the only strategy to prevent vector-borne diseases. As part of the search for novel, biological and environmentally friendly strategies for vector control, the isolation of new bacterial species with mosquitocidal activity represents a promising approach. However, new bacterial isolates may be difficult to grow and genetically manipulate. To overcome these limits, here we set up a system allowing the expression of mosquitocidal bacterial toxins in the well-known genetic background of Bacillus subtilis. As a proof of this concept, the ability of B. subtilis to express individual or combinations of toxins of Bacillus thuringiensis israelensis (Bti) was studied. Different expression systems in which toxin gene expression was driven by IPTG-inducible, auto-inducible or toxin gene-specific promoters were developed. The larvicidal activity of the resulting B. subtilis strains against second-instar Ae. albopictus larvae allowed studying the activity of individual toxins or the synergistic interaction among Cry and Cyt toxins. The expression systems here presented lay the foundation for a better improved system to be used in the future to characterize the larvicidal activity of toxin genes from new environmental isolates. 相似文献
26.
Camilla Fonseca Silva Luciana Guimarães Keyller Bastos Borges Clebio Soares Nascimento Jr. 《Chirality》2020,32(1):53-63
Dinotefuran is a low-cost agrochemical considered a highly toxic product. In this sense, there is a need for its constant environmental, biological, and food control, aiming to ensure its use to humans as well as to preserve biodiversity and ecosystems. In the present work, we developed an experimental and theoretical method for dinotefuran chiral discrimination. According to the main results, the dinotefuran enantioselective separation was efficiently optimized by high-performance liquid chromatography evaluating the influence of different percentage compositions in the mobile phase to improve the resolution of the peaks in the chromatogram. The novelty of this work was the proposition of a reduced molecular model for the chiral selector amylose-Tris-(3,5-dimethylphenylcarbamate) polysaccharide that was able to adequately describe at the molecular level its interaction with the dinotefuran enantiomers. Besides, the thermodynamic and structural parameters obtained via density functional theory calculations pointed out the chiral discrimination as well as the enantiomeric elution order of the analyte studied, confirming the experimental data, thus validating our proposed method. Finally, hydrogen bonds and repulsive interactions played a key role in the discrimination between the diastereomeric complexes, and consequently, for the dinotefuran enantioselective separation. 相似文献
27.
Berti Francesco Romano Maria Rosaria Micoli Francesca Adamo Roberto 《Glycoconjugate journal》2021,38(4):401-409
Glycoconjugate Journal - Neisseria meningitidis is a major cause of bacterial meningitidis worldwide. Children less than five years and adolescents are particularly affected. Nearly all invasive... 相似文献
28.
Beylergil Sinem Balta Murray Jordan Noecker Angela M. Gupta Palak Kilbane Camilla McIntyre Cameron C. Shaikh Aasef G. Ghasia Fatema F. 《Journal of computational neuroscience》2021,49(3):345-356
Journal of Computational Neuroscience - Miniature yoked eye movements, fixational saccades, are critical to counteract visual fading. Fixational saccades are followed by a return saccades forming... 相似文献
29.