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101.
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Tundis R Loizzo MR Statti GA Passalacqua NG Peruzzi L Menichini F 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(7-8):467-472
Alkaloid profiles of five Senecio species (Asteraceae), including S. ambiguus subsp. ambiguus, S. ambiguus subsp. nebrodensis, S. gibbosus subsp. bicolor, S. gibbosus subsp. gibbosus, and S. gibbosus subsp. cineraria, were studied. Eleven pyrrolizidine alkaloids were identified and their content was evaluated by GLC-MS and GLC analysis. Otosenine and florosenine were found to be the major alkaloids in all studied species. It is interesting that only S. ambiguus subsp. nebrodensis was characterized by a high content of the alkaloids jacobine, jacoline, jaconine, and jacozine. 相似文献
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Horseradish peroxidase in ionic liquids: Reactions with water insoluble phenolic substrates 总被引:5,自引:0,他引:5
Simona Sgalla Giancarlo Fabrizi Sandro Cacchi Alberto Macone Alessandra Bonamore Alberto Boffi 《Journal of Molecular Catalysis .B, Enzymatic》2007,44(3-4):144-148
The reactivity of horseradish peroxidase (HRP) with water insoluble phenolic compounds has been studied in 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4])/water mixtures. The enzyme retained some catalytic activity up to 90% ionic liquid in water at 25 °C only at pH values higher than 9.0. Activity steadily decreased towards neutral and acidic conditions, as judged by 4-aminoantypirin/phenol activity tests. Inhibition of horseradish peroxidase under neutral acidic condition was due to the binding of fluoride anions released from tetrafluoroborate anion to the heme iron as demonstrated by the sharp UV–visible absorption transition diagnostic of the conversion from a five coordinated to a six coordinated high spin ferric heme iron. Thus, reactions with water insoluble phenols were carried out under alkaline reaction conditions and 75% [BMIM][BF4]/water mixture. Under these conditions, the distribution of the reaction products was much narrower with respect to that observed in aqueous buffers or water/dimethylformamide or water/dimethylsulfoxide mixtures, and polymeric species other than dimers were not observed. Technical scale preparations of a novel 4-phenylphenol ortho dimer [2,2′-bi-(4-phenylphenol)] with a high yield of the desired product were obtained. 相似文献
105.
Makelele Isaac Ahanamungu Bauters Marijn Verheyen Kris Barthel Matti Six Johan Rütting Tobias Bodé Samuel Cizungu Ntaboba Landry Mujinya Bazirake Basile Boyemba Bosela Faustin Kimbesa Fabrice Ewango Corneille Boeckx Pascal 《Plant and Soil》2022,476(1-2):743-753
Plant and Soil - Many applied disciplines have recognized problems related to the practice of data analysis within their own communities. Some of them have even declared the existence of a... 相似文献
106.
Functional diversification of the dehydrin gene family in apple and its contribution to cold acclimation during dormancy 下载免费PDF全文
Vítor da Silveira Falavigna Yohanna Evelyn Miotto Henrique Pessoa dos Santos Flávio Bello Fialho Márcia Margis‐Pinheiro Giancarlo Pasquali Luís Fernando Revers 《Physiologia plantarum》2015,155(3):315-329
Dehydrins (DHN) are proteins involved in plant adaptive responses to abiotic stresses, mainly dehydration. Several studies in perennial crops have linked bud dormancy progression, a process characterized by the inability to initiate growth from meristems under favorable conditions, with DHN gene expression. However, an in‐depth characterization of DHNs during bud dormancy progression is still missing. An extensive in silico characterization of the apple DHN gene family was performed. Additionally, we used five different experiments that generated samples with different dormancy status, including genotypes with contrasting dormancy traits, to analyze how DHN genes are being regulated during bud dormancy progression in apple by real‐time quantitative polymerase chain reaction (RT‐qPCR). Duplication events took place in the diversification of apple DHN family. Additionally, MdDHN genes presented tissue‐ and bud dormant‐specific expression patterns. Our results indicate that MdDHN genes are highly divergent in function, with overlapping levels, and that their expressions are fine‐tuned by the environment during the dormancy process in apple. 相似文献
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Pehuén Pereyra Gerber Mercedes Cabrini Carolina Jancic Luciana Paoletti Claudia Banchio Catalina von Bilderling Lorena Sigaut Lía I. Pietrasanta Gabriel Duette Eric O. Freed Genevieve de Saint Basile Catarina Ferreira Moita Luis Ferreira Moita Sebastian Amigorena Philippe Benaroch Jorge Geffner Matías Ostrowski 《The Journal of cell biology》2015,209(3):435-452
During the late stages of the HIV-1 replication cycle, the viral polyprotein Pr55Gag is recruited to the plasma membrane (PM), where it binds phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and directs HIV-1 assembly. We show that Rab27a controls the trafficking of late endosomes carrying phosphatidylinositol 4-kinase type 2 α (PI4KIIα) toward the PM of CD4+ T cells. Hence, Rab27a promotes high levels of PM phosphatidylinositol 4-phosphate and the localized production of PI(4,5)P2, therefore controlling Pr55Gag membrane association. Rab27a also controls PI(4,5)P2 levels at the virus-containing compartments of macrophages. By screening Rab27a effectors, we identified that Slp2a, Slp3, and Slac2b are required for the association of Pr55Gag with the PM and that Slp2a cooperates with Rab27a in the recruitment of PI4KIIα to the PM. We conclude that by directing the trafficking of PI4KIIα-positive endosomes toward the PM, Rab27a controls PI(4,5)P2 production and, consequently, HIV-1 replication. 相似文献
110.
In vitro micropropagation by direct organogenesis and somatic embryogenesis via callus was developed for Crambe tataria (Brassicaceae). C. tataria is an endemic species of the Pontic-Pannonic region, but it is also present in Italy, where it is localized in Friuli on
a characteristic grassland formation, called “magredi”. C. tataria is regarded as an endangered species. Leaf and root explants were subjected to plant regulator treatments, which invoked
different morphogenic responses. Leaf explants produced more callus than root explants and a higher amount of callus was obtained
with 1 mg l−1 2,4-D in combination with 2 mg l−1 Kin. Somatic embryogenesis was obtained in calli maintained in a delayed subculture regime on media containing BAP in combination
with NAA. Root explants cultured with BAP combined with NAA developed adventitious rosette shoots. Shoots rooted on half-strength
MS media, and the number of roots per plantlet and their length were heavily dependent on sucrose content. The in vitro regenerated
plantlets were acclimatized ex vitro and a mean of 50% of the plantlets survived and showed a true-to-type growth habit. This
study describes the development of two in vitro micropropagation protocols, via direct organogenesis and via embryogenesis
from callus, that are the basis for the application of in vitro tools for the establishment of basal collections with representative
genetic diversity and for the long-term storage of plant genetic material. 相似文献