Effects of Lysine Acetylation in a β-Hairpin Peptide: Comparison of an Amide−π and a Cation−π Interaction
作者:Robert M. Hughes、Marcey L. Waters
DOI:10.1021/ja0648460
日期:2006.10.1
The acetylation of lysine is a common posttranslational modification of histone proteins, and the interaction of acetylated lysines with aromatic rings is commonly observed in transcriptionally relevant protein-protein interactions. To determine the nature of this interaction and its potential role in protein structure and function, the effect of lysine acetylation on its interaction with tryptophan has been investigated within the context of a beta-hairpin peptide. Acetylation of Lys results in the replacement of a cation-pi interaction with an amide-pi interaction. Despite the loss of positive charge, the interaction energy is not significantly perturbed, although the geometry of interaction is influenced such that the amide NH interacts directly with the Trp ring. Thermodynamic analysis indicates an enthalpic driving force for the stabilization, indicating a polar-pi interaction. Acyl lysine analogues formyl lysine and trifluoroacetyl lysine were used to further investigate the sterics and electronics of the interaction.
Total Synthesis and Biological Evaluation of Transvalencin Z
作者:Kathryn M. Nelson、Christine E. Salomon、Courtney C. Aldrich
DOI:10.1021/np200972s
日期:2012.6.22
is a naturalproduct from Nocardia transvalensis with relatively potent and selective antimycobacterial activity against Mycobacterium smegmatis, making it an attractive target for structure–activity and mechanism of action studies. The total synthesis of the four possible diastereomers of transvalencin Z was completed (1a–d), and the absolute configurations were defined using chemical synthesis, HPLC
耐药性结核病的新出现的全球流行病迫切需要确定新的疾病治疗方法。Transvalencin Z ( 1 ) 是来自Nocardia transvalensis的天然产物,对耻垢分枝杆菌具有相对强效和选择性的抗分枝杆菌活性,使其成为结构-活性和作用机制研究的有吸引力的目标。Transvalencin Z的四种可能的非对映异构体的全合成完成(1a - d),绝对构型是使用化学合成、HPLC 保留时间和旋光度测量定义的。令人惊讶的是,反式瓦伦星 Z 非对映异构体中没有一种对一组微生物病原体表现出任何抑制活性,包括几种分枝杆菌。