Control of Surface-Localized, Enzyme-Assisted Self-Assembly of Peptides through Catalyzed Oligomerization

Abstract

Localized self-assembly allowing both spatial and temporal control over the assembly process is essential in many biological systems. This can be achieved through localized enzyme-assisted self-assembly (LEASA), also called enzyme-instructed self-assembly, where enzymes present on a substrate catalyze a reaction that transforms noninteracting species into self-assembling ones. Very few LEASA systems have been reported so far, and the control of the self-assembly process through the surface properties represents one essential step toward their use, for example, in artificial cell mimicry. Here, we describe a new type of LEASA system based on α-chymotrypsin adsorbed on a surface, which catalyzes the production of (KL)OEt oligopeptides from a KLOEt (K: lysine; L: leucine; OEt ethyl ester) solution. When a critical concentration of the formed oligopeptides is reached near the surface, they self-assemble into β-sheets resulting in a fibrillar network localized at the interface that can extend over several micrometers. One significant feature of this process is the existence of a lag time before the self-assembly process starts. We investigate, in particular, the effect of the α-chymotrypsin surface density and KLOEt concentration on the self-assembly kinetics. We find that the lag time can be finely tuned through the surface density in α-chymotrypsin and KLOEt concentration. For a given surface enzyme concentration, a critical KLOEt concentration exists below which no self-assembly takes place. This concentration increases when the surface density in enzyme decreases.

Formation Mechanism and Biomedical Applications of Protease-Manipulated Peptide Assemblies

“…acid membrane generated the mixed product [(KL) x , x = 2-7], which self-assembled to form an entangled nanofibrillar network at the interface (Vigiercarriere et al, 2017). For this enzyme immobilization approach, there was a lag time prior to the beginning of self-assembly, which could be tuned by changing the surface density of chymotrypsin and the concentration of KL-OEt.…”

Surface‐Assisted Self‐Assembly Strategies Leading to Supramolecular Hydrogels

“…Based on work performed in solution, the same group has established in 2017 that α‐chymotrypsin confined on a surface is able to oligomerize ethyl ester dipeptides KL‐OEt (K=lysine, OEt=ethyl ester group at C‐terminal position) and produce oligopeptides (KL) n ‐OEt, which are efficient LMWHs at the surface . The growth of the self‐assembly network starts after a lag time that can easily be tuned by varying the surface density of α‐chymotrypsin and the concentration of KL‐OEt in solution.…”

Oberflächenunterstützte Selbstorganisationsstrategien für supramolekulare Hydrogele

“…Die gleiche Arbeitsgruppe berichtete 2017, dass oberflächengebundenes α‐Chymotrypsin in der Lage ist, Ethylesterpeptide KL‐OEt (K=Lysin, OEt=Ethylestergruppe in C‐terminaler Position) zu oligomerisieren und Oligopeptide (KL) n ‐OEt zu bilden, die effiziente LMWHs an der Oberfläche sind . Die Selbstorganisation beginnt nach einer Verzögerungsphase, die durch Variieren der Oberflächendichte von α‐Chymotrypsin und der Konzentration von KL‐OEt in Lösung leicht moduliert werden kann.…”

“…b) Kryo‐MEB‐Bilder des (KL) n ‐OEt‐basierten Hydrogels in z ‐Richtung. Wiedergabe mit Genehmigung . Copyright 2017, American Chemical Society.…”