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Laforce R Rigozzi K Paganetti M Mossi W Guainazzi P Calderari G 《Biological signals and receptors》1999,8(1-2):143-146
Commercially available melatonin was found to contain impurities associated with eosinophilia-myalgia syndrome (EMS). From sample analysis, remarkable differences in impurity profiles between the active ingredient from various suppliers could be found. An industrial process was developed which guarantees a high purity melatonin active ingredient. All potential impurities have been characterized and synthetized for analytical conformity with pharmaceutical regulations. To avoid any side effects from impurities, only high-purity melatonin should be utilized from the laboratory through to commercialization. 相似文献
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A crucial event in DNA replication is the polymerase switch from the synthesis of a short RNA/DNA primer by DNA polymerase alpha/primase to the pro?cessive elongation by DNA polymerase delta. In order to shed light on the role of replication factor C (RF-C) in this process, the effects of RF-C on DNA polymerase alpha were investigated. We show that RF-C stalls DNA polymerase alpha after synthesis of approximately 30 nucleotides, while not inhibiting the polymerase activity per se. This suggested that RF-C and the length of the primer may be two important factors contributing to the polymerase switch. Furthermore the DNA binding properties of RF-C were tested. Band shift experiments indicated that RF-C has a preference for 5' recessed ends and double-stranded DNA over 3' ends. Finally PCNA can be loaded onto a DNA template carrying a RNA primer, suggesting that a DNA moiety is not necessarily required for the loading of the clamp. Thus we propose a model where RF-C, upon binding to the RNA/DNA primer, influences primer synthesis and sets the conditions for a polymerase switch after recruiting PCNA to DNA. 相似文献
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Preczeski Karina P. Kamanski Angela B. Scapini Thamarys Camargo Aline F. Modkoski Tatiani A. Rossetto Vanusa Venturin Bruno Mulinari Jéssica Golunski Simone M. Mossi Altemir J. Treichel Helen 《Bioprocess and biosystems engineering》2018,41(6):851-857
Bioprocess and Biosystems Engineering - In this study, we evaluated the concentration of lipases from Aspergillus niger using efficient and low-cost methods aiming at application in the treatment... 相似文献
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Ieda Rottava Graziela Batesini Marceli Fernandes Silva Lindomar Lerin Débora de Oliveira Francine Ferreira Padilha Geciane Toniazzo Altemir Mossi Rogério Luis Cansian Marco Di Luccio Helen Treichel 《Carbohydrate polymers》2009,77(1):65-71
The proposal of the present study was to select and carry out the molecular characterization of strains of Xanthomonas sp. in order to correlate with gum production and determine possible genetic alterations during the study. The gums produced were also evaluated rheologically. Ten strains of Xanthomonas were used in the screening and the best ones in terms of productivity were Xanthomonas campestris pv. mangiferaeindicae 1230 (8.93 g/L), X. campestris pv. campestris 254 (9.49 g/L) and X. campestris pv. campestris 1078 (9.67 g/L). The gum produced by X. campestris pv. mangiferaeindicae presented the best apparent viscosity. The results for the profiles of the bands produced by RAPD showed considerable genetic variability amongst the evaluated strains, making not possible to neither group the strains according to pathovar or species, nor correlate the band profile with the productivity obtained. According to the RAPD analysis, no detectable mutations occurred in these bacteria during the study. 相似文献
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Electron microscopic analysis reveals that replication factor C is sequestered by single-stranded DNA. 总被引:1,自引:0,他引:1 下载免费PDF全文
R C Keller R Mossi G Maga R E Wellinger U Hübscher J M Sogo 《Nucleic acids research》1999,27(17):3433-3437
Replication factor C (RF-C) is a eukaryotic heteropentameric protein required for DNA replication and repair processes by loading proliferating cell nuclear antigen (PCNA) onto DNA in an ATP-dependent manner. Prior to loading PCNA, RF-C binds to DNA. This binding is thought to be restricted to a specific DNA structure, namely to a primer/template junction. Using the electron microscope we have examined the affinity of human heteropentameric RF-C and the DNA-binding region within the large subunit of RF-C from Drosophila melanogaster (dRF-Cp140) to heteroduplex DNA. The electron microscopic data indicate that both human heteropentameric RF-C and the DNA-binding region within dRF-Cp140 are sequestered by single-stranded DNA. No preferential affinity for the 3' or 5' transition points from single- to double-stranded DNA was evident. 相似文献
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Balsan G Astolfi V Benazzi T Meireles MA Maugeri F Di Luccio M Dal Prá V Mossi AJ Treichel H Mazutti MA 《Bioprocess and biosystems engineering》2012,35(7):1229-1237
This work is focused on the characterization of a commercial cellulase in terms of optimum pH and temperature, stability to pH and temperature and affinity of this enzyme to several substrates, determining the Michaelis-Menten parameters. Maximum activity of cellulase was obtained for the temperature range from 40 to 50 °C and pH from 5.2 to 5.5. Enzyme activity decreased only 15% after 150 h of reaction at temperatures between 30 and 50 °C. No loss of activity was observed at pH 5.0 and 5.5. The cellulase showed satisfactory results in the hydrolysis of agroindustrial substrates, since similar activity was verified on filter paper and other agroindustrial substrates. 相似文献
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