RESUMO
We studied the kinetics of adsorption of alexa-labeled Bt toxin Cry1Aa, in monomer and oligomer states, on muscovite mica, acid-treated hydrophilic glass, and hydrophobized glass, in the configuration of laminar flow of solution in a slit. Normal confocal fluorescence through the liquid volume allows the visualization of the concentration in solution over the time of adsorption, in addition to the signal due to the adsorbed molecules at the interface. The solution signal is used as calibration for estimation of interfacial concentration. We found low adsorption of the monomer compared to oligomers on the three types of surface. The kinetic adsorption barrier for oligomers increases in the order hydrophobized glass, muscovite mica, acid-treated hydrophilic glass. This suggests enhanced immobilization in soil if toxin is under oligomer state.
Assuntos
Silicatos de Alumínio/química , Proteínas de Bactérias/análise , Endotoxinas/análise , Vidro/química , Proteínas Hemolisinas/análise , Poluentes do Solo/análise , Adsorção , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Cromatografia Líquida de Alta Pressão , Endotoxinas/química , Corantes Fluorescentes , Proteínas Hemolisinas/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Confocal , Microscopia de Fluorescência , Compostos Orgânicos , Poluentes do Solo/química , Soluções , Propriedades de SuperfícieRESUMO
We describe and discuss the stability conditions of a naked double stranded DNA molecule starting from the evaluation of condensation or compactness fluctuation of this molecule embedded in pure water.
Assuntos
DNA/fisiologia , Modelos Genéticos , Animais , Fenômenos BiomecânicosRESUMO
Two-dimensional electrophoresis is an efficient method for the analysis of a broad range of complex protein samples. Current two-dimensional gel techniques are not suited for analysis of the small amount of proteins from tissue samples in the presence of high concentration of salts. Here we describe an improved two-dimensional gel electrophoresis procedure based on the use of a nonionic wetting agent, Tergitol NP7, in rehydration solution combined with the application of a linear potential sweep during isoelectrofocusing. This experimental approach yields a dramatic increase in the resolution and focusing of proteins visualized on two-dimensional gels. This technique is less time-consuming and laborious than the current techniques and can be used for a variety of two-dimensional electrophoresis applications, including proteome analysis.
