| Protein is the important matter of life and the direct expression of genetic traits. It can participate inDNA replication and the constitution of the frame of biological cells, and has various physiological functions, and takes an important role in life. The nucleic acid is the carrier of carrying and transferring the genetic information, and important for the growth, development of biological and genetic variation and life process. The interaction between small molecules and protein or nucleic acid is studied from molecular level, which has an important significance on drugs in the biological effects, and metabolic process of drugs, and the design of new drugs, and the development of the life information science.CPT is a plant anti-cancer drug, with anti-inflammatory and antiviral effect. But it has the strong toxic and side-effect, and its derivatives have become a hot point of research. The research status and the significance and the main methods of the interaction between CPT and biomacromolecules have been mainly introduced. This paper, the fluorescence spectrometry, the improvement of fluorescence spectrometry, uv-vis spectrophotometry and infrared spectrum method were used to nvestigate CPT interact with cow serum albumin, lysozyme, catalase, muscle protein and cytochrome C and DNA. Results have certain guiding role on the further development of research on CPT and its derivatives. The thesis is divided into the following several parts:1. The research on the fluorescence spectrum and analysis of CPT。By the standard of the fluorescence quantity irradiation 0.55 of quinine sulfate with excitation wavelength at 313 nm, in the determination conditions that pH was 7.40 and 20 degrees celsius, the fluorescence quantity irradiation of CPT were determined under different excitation wavelength, the quantum yield of fluorescence excitation wavelength at 365 nm is 0.9977. The results proved that CPT is a strong fluorescence compound.2. The research of interaction between CPT and five proteins and analysis. (1) The interaction between CPT and three kinds of protein molecules were reseached by the methord of fluorescence spectrum. LYSO, CAT and BSA are the research objects. The quenching mechanism of the three kinds protein with endogenous fluorescent by CPT was investigated, the combination constant are also found, and the ability of CPT interacts with three kinds of protein were compared according to the combination constants, and the acting force form were discussed through the thermodynamic parameters. Results show that, the forces of CPT with protein is CAT> LYSO> BSA. The affection of CPT on protein conformations were discussed by uv and synchronous fluorescence spectroscopy; (2) The interaction between CPT and BSA, CAT, LYSO, CYT, MB and CYT were studyed by fluorescence spectrometry, ultraviolet-visible spectroscopy and infrared spectrum, and CPT was the subject and five kinds of protein molecules was the object. Main reaction type:the force of LYSO-CPT is the electrostatic force, and other forces are hydrophobic force.The ability of interaction was compared and analysised by the binding constant of the systems, and the influence of CPT on protein conformation was explained through the data. Results show that, the forces of CPT with protein is CYT> MB> CAT> LYSO> BSA, which were same as the conventional fluorescence spectrometry, under the condition of in vitro experiments. (3) The methods of measurement CPT were established in the system containing these five kinds of protein, and the reliability of the method was validated by the analysis in the actual samples.3. The study of the interaction between CPT and kinds of amino acid small biomolecules. The reaction mechanism of CPT with amino acid (TRP,TYR and PHE) was studied by fluorescence spectrometry. Experimental results showed that the combination of CPT and TRP was the strongest, and the try was the weakest through comparison of the binding constants. The affection of thirteen amino acids on the fluorescence spectrometry of CPT was investigated, the results showed that CPT was held together by hydrogen bonds with these 13 kinds of amino acids, but because of the limitation of the method, the forces can't be compared.4. The study of the improved fluorescence spectroscopy on the interaction between CPT and salmon sperm DNA.The interaction between CPT and salmon sperm DNA was investigated by means of the improved fluorescence spectrometry, and the mechanism of action was discussed, and the date information of the binding constant and number of binding sites for the CPT and DNA were obtained. In conditions that pH was 7.40 and 20 degrees celsius, the binding constant at the fluorescence excitation wavelength was 252 nm and 222 nm is 4.18×104L·mol-1 and 2.36×104 L·mol-1 and the number of binding sites at the fluorescence excitation wavelength was 252 nm and 222 nm is 0.85 and 1.12; The type of interaction force of intermolecular interaction was mainly hydrophobic force, according to△S0>0 and△H0<0. The results of Uv-Vis spectrophotometry and sychronous fluorescence spectrometry indicated that CPT interacted with DNA by intercalation. According to IR of the base and phosphoric acid:the IR peak of base at 1693 cm-1 and phosphoric acid at 1063 cm-1,1230 cm-1 moved to 1631 cm-1,1058 cm-1 and 1289 cm-1, the experimental results showed that the interaction of CPT with the bases and phosphate groups of DNA changed the B configurations of DNA.5. The interaction between CPT and DNA was studied by the fluorescent probe of acetamiprid orange. The interaction between CPT and DNA was investigated using the fluorescence probe of acetamiprid orange (AO) under the physiological conditions, as well as the absorption spectra of DAN. The results of salteffectanion, luminescence quenchers KI, phosphate, competition tests, viscosity tests, inhibitory rate and denatured tests have indicated that CPT was bound to DNA by the mode of intercalation or the mode of groove binding, and the mode of intercalation was the mainly of intercalation mode.
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