Multivalent Peptide and Protein Dendrimers Using Native Chemical Ligation

Abstract

Eine Vielzahl gut definierter multivalenter Peptide und Proteine ist erhältlich, indem synthetische Peptide und rekombinant exprimierte Proteine mithilfe der nativen chemischen Ligation an Cystein‐funktionalisierte Dendrimere konjugiert werden (siehe Bild). Auf diesem Weg sind Dendrimere zugänglich, die für das Verständnis zentraler Aspekte der Multivalenz in biologischen Wechselwirkungen wie auch für biomedizinische Anwendungen interessant sind.

Branched KLVFF Tetramers Strongly Potentiate Inhibition of β‐Amyloid Aggregation

“…[28] Standard tert-butyloxycarbonyl (t-Boc)-mediated solidphase peptide synthesis was used to make the KLVFFGG peptide. The two glycine residues (GG) were included to provide a spacer between the KLVFF sequence and the dendrimer structure.…”

“…The two glycine residues (GG) were included to provide a spacer between the KLVFF sequence and the dendrimer structure. The KLVFFGG peptides were functionalized with a C-terminal mercaptopropionic acid leucine (MPAL) thioester, as described in Hackeng et al [39] Functionalization of the amine-terminated poly(propylene imine) dendrimers (kindly provided by DSM (Geleen, The Netherlands)) with cysteine residues, was done as described in van Baal et al [28] Four equivalents of peptide thioester were ligated to one equivalent of the cysteine dendrimer by using standard ligation conditions (Tris buffer pH 7.5, 6 m guanidine, 2 % (v/v) thiophenol, 2 % A C H T U N G T R E N N U N G (v/v) benzylmercaptan, 37 8C), with stirring for 1 h at 37 8C. This resulted in the formation of [KLVFFGG] 4 dendrimer.…”

“…This resulted in the formation of [KLVFFGG] 4 dendrimer. The ligation product was further purified by using reversed-phase HPLC as described in van Baal et al [28] The cysteine dendrimer is referred to as C 4 , KLVFFGG is referred to as K 1 and the [KLVFFGG] 4 dendrimer is reA C H T U N G T R E N N U N G ferred to as K 4 . As an additional control in the aggregation experiments, we used a dendrimer with 4 copies of the unrelated pentapeptide GRGDS with GG as a spacer (G 4 ).…”

“…As an additional control in the aggregation experiments, we used a dendrimer with 4 copies of the unrelated pentapeptide GRGDS with GG as a spacer (G 4 ). [28] All peptides and peptide dendrimers were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, by using a-cyano-4-hydrocinnamic acid as a matrix. The MS data of the K 1 and K 4 structures are shown in the supplementary data.…”

“…Dendrimers are multivalent macromolecules with regular, highly branched structures and dimensions that resemble those of small proteins; they have been used in several different biological applications. [27] In this study we have synthesized a firstgeneration KLVFF dendrimer by using native chemical ligation, [28] thereby generating a small, well-defined molecule that is capable of making multivalent interactions. We have investigated the effect of dendritic KLVFF on the aggregation of low molecular weight (LMW) Ab 1-42 as well as its effects on preformed aggregates.…”