色氨酸与功能单体自组装体系的分子间非共价相互作用

Non-covalent Interaction of Tryptophan with Functional Monomers in Self-assembly Systems

利用荧光猝灭分析、三维荧光光谱和计算机模拟等方法分别研究色氨酸(L-Trp)与己二酸二酰肼(ADH)、双丙酮丙烯酰胺(DAAM)和丙烯酸(AA)3种功能单体间的非共价相互作用.考察了荧光猝灭机理、色氨酸-功能单体的相互作用强弱以及作用力类型.研究结果表明,功能单体对L-Trp的荧光猝灭过程是由于形成不发射荧光的复合物而引起的静态猝灭;L-Trp与功能单体的结合常数较大,所形成的复合物较稳定,非共价作用中以氢键和静电作用贡献最大;L-Trp主要通过羧基与功能单体产生相互作用,芳杂环与功能单体间的相互作用相对较弱;L-Trp与功能单体相互作用的强弱顺序为L-Trp-ADH>L-Trp-DAAM>L-Trp-AA.

The non-covalent interaction of tryptophan（L-Trp） with adipic dihydrazide （ADH）, diacetone ac- rylamide（DAAM） or acrylic acid （AA） was investigated by fluorescence quenching, three-dimensional fluo- rescence spectrum in combination with computer simulation, respectively. The quenching mechanism, the strength and types of interaction force between L-Trp and functional monomers were studied. The results showed that the fluorescence of L-Trp was quenched through a static quenching procedure by functional mono- mer due to the formation of L-Trp-functional monomer complexes. The complexes had high binding constant and exhibited good stability. The non-covalent interaction between L-Trp and functional monomers was domi- nated by hydrogen bond and electrostatic force. The binding site in L-Trp was supplied largely by carboxyl group rather than heteroaromatic ring. The strength of interaction between L-Trp and functional monomers was in the following order： L-Trp-ADH〉L-Trp-DAAM〉L-Trp-AA.