Kinetics and Thermodynamics of Binding of a Model Tripeptide to Teicoplanin and Analogous Semisynthetic Antibiotics
作者:Paolo Scrimin、Paolo Tecilla、Umberto Tonellato、Massimo Verzini、Bianca Patrizia Andreini、John E. Coutant、Luigi F. Zerilli
DOI:10.1021/jo9605556
日期:1996.1.1
thermodynamics and kinetics of binding of model tripeptides epsilon-N-acetyl-alpha-N-dansyl-L-Lys-D-Ala-D-Ala (ADLAA) or alpha-N,epsilon-N-diacetyl-L-Lys-D-Ala-D-Ala (AALAA) to teicoplanin (1a) and a series of semisynthetic derivatives with (1b-f) or devoid of (2a-g) the glycidic side arms and modified at the terminal amino acids of the peptide backbone have been studied by fluorescence or UV spectroscopy. The binding
模型三肽ε-N-乙酰基-α-N-丹酰-L-Lys-D-Ala-D-Ala(ADLAA)或α-N,ε-N-二乙酰基-L-Lys-的结合的热力学和动力学替考拉宁(1a)的D-Ala-D-Ala(AALAA)和一系列具有(1b-f)或不含(2a-g)糖苷侧臂并在肽主链末端氨基酸修饰的半合成衍生物已经通过荧光或紫外光谱研究。建议绑定过程通过两步机制进行。第一个快速过程很可能分别受底物肽链和抗生素肽链的C和N末端之间的静电相互作用支配,而第二个较慢的过程则解释了氢键的形成对整体约束力的主要贡献。所有修饰衍生物的结合常数均小于天然替考拉宁的结合常数。当除去糖残基时,观察到总结合常数的较大变化,而当肽链的N端被酰化时,观察到较小程度的变化。动力学过程受引入的修饰影响很小。