1 |
Applications of NMR techniques: Hyphenations (LC-SPENMR), affinity (DOSY) and NOE based (STD and Tr-OESY) to probe the binding interactions of ligands (synthetic and natural) towards proteinAhmad, Sheraz 17 January 2014 (has links)
Made available in DSpace on 2016-06-02T20:34:49Z (GMT). No. of bitstreams: 1
5686.pdf: 10016184 bytes, checksum: e6a42772f0db7983f4cc9525851f9c5b (MD5)
Previous issue date: 2014-01-17 / Universidade Federal de Sao Carlos / O foco principal desse trabalho foi a implementação, otimização e aplicações práticas de métodos de ressonância magnética nuclear (RMN) com o propósito de avaliar as interações entre moléculas de diferentes massas molares, sendo que essas técnicas foram implementadas pela primeira vez no laboratório de RMN do DQ-UFSCar. Existem várias abordagens que podem ser utilizadas com esse propósito, e dentre elas, destacamos: STD NMR, Tr-NOESY, WaterLOGSY, SALMON, INPHARMA, DOSY, SAR. Esses métodos são muito úteis para detectar mudanças de comportamento, a nível molecular, quando adicionamos macromoléculas em um meio contendo somente micromoléculas. O entendimento desse comportamento molecular ajuda a desvendar sistemas complexos de interações moleculares existentes no corpo humano, e que, são muito importantes para o descobrimento de novos medicamentos. O primeiro passo para a implementação das técnicas foi a utilização da proteína de soro bovino (do inglês BSA) e proteína de soro humano (do inglês HSA) como fonte de macromoléculas e micromoléculas orgânicas isoladas da fração etanólica do extrato bruto (1 mg) de Rauia resinous e da fração acetato de etila de Strypnodendron polyphyllum, utilizando cromatografia líquida de alta eficiência, extração por fase sólida e a ressonância magnética nuclear (CLAE-EFS/RMN) para a completa elucidação estrutural quando necessário. As técnicas utilizadas foram: saturation transfer difference (STD), transfer nuclear Overhauser spectroscopy (Tr-NOESY) e STD-TOCSY (total correlation spectroscopy). Essa mesma metodologia além de representar um importante mecanismo para avaliar as interações entre moléculas, também pode ser utilizada para outras matrizes variando tanto as macro quanto as micromoléculas. / The main focus of this work was the implementation, optimization and practical applications of nuclear magnetic resonance (NMR) methods for the purpose of evaluating the interactions between molecules of different masses, and these techniques were implemented for the first time in the laboratory NMR DQ - UFSCAR. There are a number of ligand-based screening approaches available, such that, STD NMR, Tr-NOESY, WaterLOGSY, SALMON, INPHARMA, DOSY, SAR by NMR etc. These methods are sensitive towards the perturbations as results of the macromolecular addition in a medium containing the small molecules. The molecular understanding of this behavior helps to uncover the complex systems of molecular interactions existing in the human body, which are very important for the discovery of new medicines. In the first step while implementing these techniques, Bovine Serum Albumin (BSA) and Human Serum Albumin (HSA) as a source of organic macromolecules were used. While, for the small organic molecules, a 1 mg crude extract from the hydroethanolic fraction of the Rauia resinous and ethyl acetate fraction of Strypnodendron polyphyllum was utilized, however, for the complete structural characterization, solid phase extraction following high-pressure liquid chromatography in an integrated fashion and then nuclear magnetic resonance (LC-SPE/NMR) was employed when necessary. On the other hand, the ligand screening techniques used were the saturation transfer difference (STD), Nuclear Overhauser Transfer Effect SpectroscopY (Tr- NOESY), Diffusion-Order Spectroscopy (DOSY) and STD- TOCSY (TOtal Correlation SpectroscopY). More importantly, this methodology also represents an important mechanism to evaluate the interactions between molecules or the first hand detection of the active constituents/inhibitors, which can also be used for other matrices varying both the macro and the small molecules.
|
Page generated in 0.0123 seconds