Chemoselective Bioconjugation of Triazole Phosphonites in Aqueous Media
作者:M. Robert J. Vallée、Paul Majkut、Dagmar Krause、Michael Gerrits、Christian P. R. Hackenberger
DOI:10.1002/chem.201404690
日期:2015.1.12
versatile phosphonite building blocks with improved stability against hydrolysis were used for the efficient metal‐free functionalization of peptides and proteins in aqueous buffers at low micromolar concentrations. The application of this protocol to the immobilization of a Rasa1‐SH2 domain revealed high binding affinity to the human T‐cell protein ADAP and supports the applicability of triazole phosphonites
作者:Alan M. Marmelstein、Jeremy A. M. Morgan、Martin Penkert、Daniel T. Rogerson、Jason W. Chin、Eberhard Krause、Dorothea Fiedler
DOI:10.1039/c8sc01233d
日期:——
striking proclivity of the phosphorimidazolides to preferentially react with phosphate monoesters over other nucleophilicsidechains. Besides enabling the characterization of pyrophosphorylation on protein function, this work highlights the utility of phosphoryl groups as handles for selective protein modification for a variety of applications, such as phosphoprotein bioconjugation and enrichment.
阐明蛋白质翻译后修饰 (PTM) 功能的一个重要步骤是获得位点特异性修饰的均质样品以进行生化表征。蛋白质焦磷酸化是一种尚不清楚的 PTM,本文报道了一种获得焦磷酸蛋白的化学方法。开发了光不稳定的磷咪唑试剂,用于焦磷酸蛋白的选择性焦磷酸化、亲和捕获和释放。反应动力学分析揭示了9.2 × 10 -3至0.58 M -1 s -1之间的速率常数,以及与其他亲核侧链相比,磷咪唑化物优先与磷酸单酯反应的显着倾向。除了能够表征焦磷酸化对蛋白质功能的影响外,这项工作还强调了磷酰基作为选择性蛋白质修饰手柄的实用性,适用于各种应用,例如磷蛋白生物共轭和富集。
Quantitative Analysis of Cu(I) Concentration in Click Chemistry — Biotinylation at Side Chain of Propargylglycine Using Click Chemistry under Heating Conditions —
The click reaction is one of the latest techniques for the chemical modification of bioactive compounds. Chemical modifications of alpha-amino acid side chains are gaining significance as useful and important tools for biochemical research. Biotinylation at side chain of propargylglycine using click reaction was examined. The detail quantitative analysis of Cu(I) concentration are performed to proceed the click reaction effectively.
Affinity-Based Screening of Peptides Recognizing Assembly States of Self-Assembling Peptide Nanomaterials
Novel peptides capable of binding to self-assembled peptide nanomaterials were identified from a random heptapeptide library displayed on phages. Affinity-dependent peptide screening against helically coiled nanofibers; constructed of beta-sheet peptides gave phage clones displaying peptides with a variety of affinities and selectivities. An enzyme-linked immunosorbent assay using phage-displayed peptides; revealed that the screened peptides specifically bind to target nanofibers, in contrast to reference nanofibers comprised of peptides with slightly different amino acid sequences. A Dot blot assay using chemically synthesized peptides demonstrated that peptide 01 (p01), with the sequence Thr-Gly-Val-Lys-Gly-Pro-Gly, showed an affinity constant (3.7 x 10(5) M-1) for the target nanofibers 200 times greater than its affinity for monomeric peptides and 60 times greater than for short nanofibers. These results suggested that p01 selectively recognizes the assembly state of the target peptide. ATR/IR secondary structure analyses clearly showed that when p01 binds to target nanofibers, it undergoes a structural transition from random-coil to parallel beta-sheet structures, resulting in greater affinity and high specificity for the target fiber. Surface modification of the peptide nanofibers by p01 demonstrated that the peptide specifically binds to the edge of the nanofibers. Using p01, uniform arrays of gold nanoparticles (proteins) could be generated on the peptide nanomaterials.
Biotin-functional oligo(p-phenylene vinylene)s synthesized using click chemistry
作者:Neeraja Vundyala、Chivin Sun、Francoise Sidime、Wei Shi、William L’Amoreaux、Krishnaswami Raja、Ralf M. Peetz
DOI:10.1016/j.tetlet.2008.08.080
日期:2008.11
Using Cu(1)-catalyzed [3+2] Huisgen 'click' cycloaddition, a rigid rod - like oligo(p-phenylene vinylene) (OPV) was functionalized at both ends with biotin ligands, combining the valuable electro-optical properties of conjugated organic molecules with the biological recognition capability of biotin. Biotin can be placed at variable distances from the oligomer via appropriate length of a hydrophilic spacer, which also serves to regulate the binding capabilities of the two terminal biotin units. To demonstrate this binding potential, networks were formed with streptavidin-coated quantum dots. The synthetic conditions are presented, together with representative optimizations of the key reactions. The organic compounds were analyzed by means of ATR/FTIR, H-1 NMR (200 or 600 MHz), C-13 NMR, 2D NMR (HMBC, HMQC experiments), MS (ESI OF MALDI-TOF), and optical spectroscopy. Networks were imaged with TEM. (C) 2008 Elsevier Ltd. All rights reserved.