CAJ | 학술논문

利用多种荧光光谱法、紫外光谱法并结合分子模拟等方法，表征了模拟生理条件下一种植物药活性组分考拉维酸(KA)影响人血清白蛋白(HSA)的结构信息。同步荧光及紫外光谱证实考拉维酸的存在影响了HSA的微环境；二维及三维荧光光谱表明考拉维酸可以猝灭HSA的内源荧光，使其构象发生变化。荧光偏振的测定提供了考拉维酸与HSA作用后生成的配合物弛豫时间与聚集特性的信息，揭示KA的存在使HSA的流动性和微粘度发生变化。定量求得不同温度下(298、308和318 K)考拉维酸与HSA作用的键合参数和热力学参数。分子模拟表明考拉维酸键合位点于HSA分子的疏水腔内，并与赖氨酸Lys195和天冬氨酸Asp451形成三个氢键，与HSA的键合模式主要是疏水作用；位点竞争实验证明考拉维酸在HSA亚结构域的位点II位发生作用。另外，获得的相关物理化学参数从分子水平上揭示了考拉维酸与HSA相互作用的机制。结果表明， HSA对考拉维酸有较强的结合能力，提示人血清白蛋白对考拉维酸可起到储存和转运的作用。
이용다충형광광보법、자외광보법병결합분자모의등방법，표정료모의생리조건하일충식물약활성조분고랍유산(KA)영향인혈청백단백(HSA)적결구신식。동보형광급자외광보증실고랍유산적존재영향료HSA적미배경；이유급삼유형광광보표명고랍유산가이졸멸HSA적내원형광，사기구상발생변화。형광편진적측정제공료고랍유산여HSA작용후생성적배합물이예시간여취집특성적신식，게시KA적존재사HSA적류동성화미점도발생변화。정량구득불동온도하(298、308화318 K)고랍유산여HSA작용적건합삼수화열역학삼수。분자모의표명고랍유산건합위점우HSA분자적소수강내，병여뢰안산Lys195화천동안산Asp451형성삼개경건，여HSA적건합모식주요시소수작용；위점경쟁실험증명고랍유산재HSA아결구역적위점II위발생작용。령외，획득적상관물이화학삼수종분자수평상게시료고랍유산여HSA상호작용적궤제。결과표명， HSA대고랍유산유교강적결합능력，제시인혈청백단백대고랍유산가기도저존화전운적작용。
The effect of Kolavenic acid (KA), an active component isolated from the genus Polyalthia, on the structure of human serum albumin (HSA) was investigated by fluorescence polarization, synchronous fluorescence, three-dimensional (3D) fluorescence, and absorption spectroscopy in combination with molecular modeling techniques under physiological conditions. The synchronous and absorption fluorescence spectra confirmed that KA has an effect on the microenvironment around HSA in aqueous solution. The two-dimensional (2D) and 3D fluorescence spectra showed that KA could quench the intrinsic fluorescence of HSA and make its conformation change. Fluorescence polarization measurements provided useful information on the relaxation time and aggregation behavior of the complex formed between HSA and KA, and indicated that the presence of KA caused changes in the fluidity and microviscosity of HSA. The binding constants and thermodynamic parameters for KA-HSA systems were obtained under different temperatures (298, 308, and 318 K). Molecular docking showed that the KA moiety bound to the hydrophobic cavity of HSA, and there were three hydrogen-bonding interactions between KA and the Lys195 and Asp451 residues. Fluorescent displacement measurements confirmed that KA bound to HSA at site II. In addition, the binding mechanism of KA and HSA was revealed by the physicochemical parameters at the molecular level. The results showed that the interaction between KA and HSA was strong, indicating that KA may be stored and transferred by serum albumin.