Método e sistema para predição de funções de proteínas

DepositadaA presente invenção refere-se a métodos e sistemas relacionados à predição da função de sequência de aminoácidos oriundas de abordagens genômicas, metagenômicas, proteômicas e transcriptômicas em larga escala. O método para predição da função de uma proteína, a partir de uma sequência de aminoácidos, que compreende a predição direta a partir da sequência de aminoácidos e a predição a partir da estrutura tridimensional da referida sequência de aminoácidos com a posterior comparação entre as duas para gerar o resultado

Caracterización parcial del proteoma del trofozoíto de Plasmodium falciparum bajo tratamiento con quinina, mefloquina y el compuesto natural diosgenona

Introduction: Despite efforts to control malaria, around 10% of the world population is at risk of acquiring this disease. Plasmodium falciparum accounts for the majority of severe cases and deaths. Malaria control programs have failed due to the therapeutic failure of first-line antimalarials and to parasite resistance. Thus, new and better therapeutic alternatives are required. Proteomic analysis allows determination of protein expression levels under drug pressure, leading to the identification of new therapeutic drug targets and their mechanisms of action.Objective: The aim of this study was to analyze qualitatively the expression of P. falciparum trophozoite proteins (strain ITG2), after exposure to antimalarial drugs, through a proteomic approach.Materials and methods: In vitro cultured synchronized parasites were treated with quinine, mefloquine and the natural antiplasmodial diosgenone. Protein extracts were prepared and analyzed by two-dimensional electrophoresis. The differentially expressed proteins were selected and identified by MALDI-TOF mass spectrometry.Results: The following proteins were identified among those differentially expressed in the parasite in the presence of the drugs tested: enolase (PF10_0155), calcium-binding protein (PF11_0098), chaperonin (PFL0740c), the host cell invasion protein (PF10_0268) and proteins related to redox processes (MAL8P1.17). These findings are consistent with results of previous studies where the parasite was submitted to pressure with other antimalarial drugs.Conclusion: The observed changes in the P. falciparum trophozoite protein profile induced by antimalarial drugs involved proteins mainly related to the general stress response.Introducción. A pesar de los esfuerzos para controlar la malaria, esta sigue siendo un problema de salud pública. Plasmodium falciparum es responsable de la mayoría de los casos graves y de las muertes. Los programas de control de la malaria han sido cuestionados debido al fracaso del tratamiento y a la resistencia del parásito a los antipalúdicos de primera línea, por lo que se requieren nuevas y mejores alternativas. El análisis proteómico permite identificar y determinar los niveles de expresión de las proteínas bajo la presión de los medicamentos, lo que posibilita la identificación de nuevos blancos terapéuticos y mecanismos de acción.Objetivo. Analizar cualitativamente la expresión diferencial de proteínas del citosol del trofozoíto de P. falciparum bajo tratamiento con quinina, mefloquina y el compuesto natural diosgenona mediante una aproximación proteómica.Materiales y métodos. Se trataron trofozoítos sincronizados y cultivados in vitro de P. falciparum (cepa ITG2) con quinina, mefloquina y el compuesto natural diosgenona. Los extractos proteicos se prepararon y analizaron por electroforesis bidimensional. Las proteínas con aparente expresión diferencial se seleccionaron e identificaron mediante espectrometría de masas MALDI-TOF.Resultados. Se encontraron las siguientes proteínas diferencialmente expresadas en el trofozoíto: la enolasa (PF10_0155), la proteína de unión a calcio (PF11_0098), la chaperonina (PFL0740c), la proteína de invasión a la célula del huésped (PF10_0268) y la proteína relacionada con procesos de reducción y oxidación (redox) (MAL8P1.17). Estos hallazgos son congruentes con resultados previos de estudios en los que el parásito fue presionado con otros medicamentos antipalúdicos.Conclusión. Los cambios observados en el perfil de proteínas del trofozoíto de P. falciparum tratado con antipalúdicos involucraron preferencialmente proteínas relacionadas con la respuesta al estrés general

Structural Changes of the Paraflagellar Rod during Flagellar Beating in Trypanosoma cruzi

, the agent of Chagas disease, is a protozoan member of the Kinetoplastidae family characterized for the presence of specific and unique structures that are involved in different cell activities. One of them is the paraflagellar rod (PFR), a complex array of filaments connected to the flagellar axoneme. Although the function played by the PFR is not well established, it has been shown that silencing of the synthesis of its major proteins by either knockout of RNAi impairs and/or modifies the flagellar motility.Here, we present results obtained by atomic force microscopy (AFM) and transmission electron microscopy (TEM) of replicas of quick-frozen, freeze-fractured, deep-etched and rotary-replicated cells to obtain detailed information of the PFR structures in regions of the flagellum in straight and in bent state. The images obtained show that the PFR is not a fixed and static structure. The pattern of organization of the PFR filament network differs between regions of the flagellum in a straight state and those in a bent state. Measurements of the distances between the PFR filaments and the filaments that connect the PFR to the axoneme as well as of the angles between the intercrossed filaments supported this idea.Graphic computation based on the information obtained allowed the proposal of an animated model for the PFR structure during flagellar beating and provided a new way of observing PFR filaments during flagellar beating

On the electrochemical hydrodynamics of fluid interfaces-stability and surface waves

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

On the electrochemical hydrodynamics of fluid interfaces-stability and surface waves

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Formal Results on the Susceptibility of Dilute Alloys. I. Green's Function Approach

The susceptibility of conduction electrons of dilute alloys is discussed including both electron–electron interactions and one‐electron impurity potentials. Adopting a two band model (s–d bands) a formal result is obtained for the partial susceptibilities, using the Green's function formalism and the Hartree‐Fock approximation. This solution is given in terms of a power series involving the Coulomb interaction and impurity parameters. An approximation is proposed, corresponding to a maximum exchange enhancement, for summing the power series, and an effective Coulomb scattering is obtained (for the fluctuations in the host) mediating the impurity scattering process. Copyright © 1976 WILEY‐VCH Verlag GmbH & Co. KGaASCOPUS: ar.jFLWNAinfo:eu-repo/semantics/publishe

Formal Results on the Susceptibility of Dilute Alloys. II. Mean‐Field Approach and Applications

A mean field approach is adopted and a matrix formulation is used to obtain formal results for the susceptibility of a two band system (α, β). This general result includes the intra‐atomic Coulomb repulsions, one‐electron impurity potentials, and the change in the Coulomb interaction and inter‐band exchange at impurity site. The complete evaluation of the partial susceptibilities involves the calculation of inverse matrices, which is difficult to perform in the general case. Expressions for the self‐polarization hyperfine field, the Knight‐shift, and ESR g‐shift are obtained for transition metal like systems (s‐d bands), using previous results obtained in I. It is shown that these quantities may be evaluated in terms of phase‐shift, involving only the density of states and the parameters of the problem. Copyright © 1976 WILEY‐VCH Verlag GmbH & Co. KGaASCOPUS: ar.jFLWNAinfo:eu-repo/semantics/publishe

On the dynamic stability of fluid dielectric films

A simplified model of a fluid dielectric (hydrocarbon) film is introduced suitable for investigating the influence of electrical forces on the dynamics and film stability. Electrical and long range van der Waals interactions are treated as body forces. Linear stability analysis is carried through for a mechanically symmetric film with (i) symmetric surface charge distribution and (ii) linear electric potential drop across the film. Results in the limit of negligible viscosities call for special attention to repulsive interaction mechanisms in dielectric films free of charge. © 1981.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Stability of low tension interfaces and propagation of longitudinal waves: role of the electrical double layers

info:eu-repo/semantics/publishe