Studies On The Interaction Between Proteins And PAAC(a Novel Content In Dune Reed)

Protein was important life material, it had osculating connection with life activities including nutrition, development, heredity and metabolism etc. Many kinds of small molecules can interact with proteins. Using these interactions one could explore and understand the inner structures, functions as well as transformations, interaction process with small molecules of those biologic macromolecules, and observing interactions and absorptions of corresponding small molecules also has important theoretic and practical values to study the stability under adverse environment of those macromolecules.Affinity chromatography, which uses coupled affinity immobilized medium to absorb target products, is a method of liquid chromatography to obtain separated and purified target products. Affinity chromatography has been used to analyze the species and quantity of the adsorbate, and, with other evidence obtained, to explore the potential interaction pattern and forces implicated between the ligand and adsorbate.This experiment with PAAC as a ligand binding to affinity column studied combining character of the soluble proteins of swamp reed lamina, which dose not contain PAAC, under immobilized conditions. The main work is as follows:The dune reed (phragmites communis Trin.) was adopted as the materials for the purification of PAAC (polyamine aromatic compound), and lamina of a swamp reed of contemporaneity and at the same area of the dune reed, which grow up in a relatively good condition, was adopted as experimental materials. By means of affinity chromatography explored potential interactions between soluble proteins of swamp reed lamina and PAAC, a small novel molecule contained only in dune reed.Being small molecule, PAAC can bind with Sepharose by activated and catalyzed of CNBr, to obtain immobilized medium coupled with the ligand of PAAC. Some of soluble proteins of swamp reed lamina, which had absorbed to affinity column to uniquely combine with PAAC, could be eluted off under different conditions. Analyzing these conditions could explore their potential interactions, interaction forces as well as the strengths between PAAC与soluble proteins of swamp reed lamina. Found that the interactions between them were mainly through ionic bond with complement of hydrogen bond, and the phyletic specificity of proteins concerning was not clear.The interactions between them as well as the possible allosteric effect were also testified by us in this experiment through supplement spectroscopy methods of Fluorescence and Circular Dichroism etc.In this experiment we testified the fluorescence quenching of proteins by PAAC was static quenching which created PAAC-proteins complex, calculated the binding constants and numbers of binding sites of PAAC and proteins, testified there were binding action between them. Offered favorable conditions for further clarify the protection of PAAC to proteins.