作者:Michael A. McMechen、Evan L. Willis、Preston C. Gourville、Caroline Proulx
DOI:10.3390/molecules24101919
日期:——
model peptide (H-Arg-Tyr-Val-Glu-Val-d-Pro-Gly-Orn-Lys-Ile-Leu-Gln-NH2) is reported. Specifically, analogs in which valine3 was substituted for aza-valine3 or aza-glycine3 were synthesized, and their β-hairpin stabilities were examined using NuclearMagneticResonance (NMR) spectroscopy. The azapeptide analogs were found to destabilize β-hairpin formation compared to the parent peptide. The aza-valine3
N-Amination Converts Amyloidogenic Tau Peptides into Soluble Antagonists of Cellular Seeding
作者:Kamlesh M. Makwana、Matthew P. Sarnowski、Jiayuan Miao、Yu-Shan Lin、Juan R. Del Valle
DOI:10.1021/acschemneuro.1c00528
日期:2021.10.20
neurofibrillary tangles composed of tau protein aggregates is a hallmark of Alzheimer’s and related neurodegenerative diseases. Early oligomerization of tau involves conformational reorganization into parallel β-sheet structures and supramolecular assembly into toxic fibrils. Despite the need for selectiveinhibitors of tau propagation, β-rich proteinassemblies are inherently difficult to target with
由 tau 蛋白聚集体组成的神经原纤维缠结的扩散是阿尔茨海默病和相关神经退行性疾病的标志。 tau 蛋白的早期寡聚涉及构象重组为平行 β 片层结构以及超分子组装为有毒原纤维。尽管需要选择性的 tau 增殖抑制剂,但富含 β 的蛋白质组装体本质上很难用小分子靶向。在这里,我们描述了一种模仿 tau 内易于聚合的模块的极简方法。我们进行了主链残基扫描,结果表明酰胺 N-氨基化完全消除了这些肽自我聚集的倾向,使它们成为 tau R2 和 R3 结构域有序 β 链的可溶模拟物。几种 N-氨基肽 (NAP) 在体外抑制 tau 原纤维形成。我们进一步证明,NAP 12和13通过与细胞外 tau 的单体或纤维形式相互作用,可有效阻断内源 tau 的细胞播种。拟肽12血清稳定,对神经元细胞无毒,并且相对于 Aβ 42选择性抑制 tau 纤维化。我们的先导 NAP 的结构分析显示 N-氨基施加了相当大的构象限制。所描述的骨架
Benzotriazole-Assisted Solid-Phase Assembly of Leu-Enkephalin, Amyloid β segment 34−42, and other “Difficult” Peptide Sequences
作者:Alan R. Katritzky、Danniebelle N. Haase、Jodie V. Johnson、Alfred Chung
DOI:10.1021/jo8026214
日期:2009.3.6
Microwave-assisted solid-phase syntheses of six "difficult" peptides, H-VVSVV-NH(2) (3), H-VVVSVV-NH(2) (4), H-VIVIG-OH (5), H-TVTVTV-NH(2) (6), H-VKDGYI-NH(2) (7), and H-VKDVYI-NH(2) (8), were achieved utilizing N-(Fmoc-(alpha-aminoacyl)benzotriazoles. Extension to the syntheses of Leu-enkephalin (9) and amyloid-beta (34-42) (10) demonstrates that this strategy comprises an efficient route to new and known "difficult" peptides.
[(9-Fluorenylmethyl)oxy]carbonyl (Fmoc) amino acid chlorides in solid-phase peptide synthesis
作者:Louis A. Carpino、Hann Guang Chao、Michael Beyermann、Michael Bienert
DOI:10.1021/jo00008a012
日期:1991.4
FMOC amino acid chlorides, previously shown to be rapid-acting coupling agents in two-phase systems or in homogeneous solution, did not prove to be directly applicable to solid-phase peptide synthesis due to sluggish reactivity. The problem was traced to prior conversion of the acid chlorides by necessary basic co-reactants (DIEA, NMM, etc.) to the corresponding oxazolones. If, in their place, 1:1 mixtures of these bases and HOBt were used, rapid solid-phase acylations were possible via the intermediate formation of the corresponding HOBt esters. The 1:1 base-HOBt mixtures also were shown to enhance generally the reactivity of FMOC amino acid active esters over that caused by HOBt alone. Peptides assembled from acid chlorides by using these techniques included leucine enkephalin, the ACP decapeptide (65-74), prothrombin (1-9), several substance P analogues, and eledoisin. Where particular acid chlorides could not be used due to their instability, the corresponding pentafluorophenyl esters or mixtures of the acids and BOP reagent were used.