Role of Thermolysin in Catalytic-Controlled Self-Assembly of Fmoc-Dipeptides

Abstract

In recent years, short peptide self-assembled materials, prepared under the control of the thermolysin catalyst, have been investigated extensively and shown to acquire various morphologies and functions as building blocks for a wide range of biomaterials and device applications. However, the role played by thermolysin in this enzymatically triggered peptide self-assembly is still ambiguous. Herein, we designed a series of Fmoc-dipeptide amphiphiles to explore the catalytic role of thermolysin. The results from our experiments and computational simulations showed that hydrophobicity and amino acid sequences of substrates have a significant correlation with thermolysin actions, including the binding capacity and catalytic efficiency. Specifically, thermolysin favors a specific substrate pattern with a hydrophilic amino acid in the first residue and hydrophobic amino acid in the second residue. Moreover, thermolysin catalyzed reactions are bidirectional and could move toward hydrolysis or condensation based on the design of its diverse substrates (peptides). However, the specificity of the enzyme action lies in the major site of its cleavage, which is the terminal hydrophobic or bulky amino side chains. We designed a two-step reaction, taking advantage of the bidirectional catalytic actions of thermolysin, to modify the sequence of N α-fluorenylmethoxycarbonyl (Fmoc)-dipeptide from Fmoc-YL-COOH to Fmoc-YY-NH 2 and treated with thermolysin, which resulted in the enzyme-catalyzed gel-sol-gel transition. This work has an instructive significance in the regulation of peptide sequences, secondary amino acid structures, morphology, and the mechanical property of self-assembled hydrogels with precise design and control at the molecular level via thermolysin catalysis.

The Impact of Tyrosine Iodination on the Aggregation and Cleavage Kinetics of MMP-9-Responsive Peptide Sequences

“…The steric and electronic effects introduced by iodotyrosine can likely alter the interactions between the peptide sequences and the binding site of the MMP-9 enzyme . Charge and polarity have an influence on the affinity of the enzyme for the peptide, ,,,, as illustrated by comparing P1 and P2 . P1 undergoes rapid hydrolysis, whereas the addition of an N -terminal positively charged lysine (K) in P2 completely inhibits hydrolysis.…”

Self-assembled Structures Formed by Fmoc modified aliphatic amino acids

“…Another study done by Sato et al reported the self-assembly Fmoc-lysine in DMSO: water mixture 33 and Bai et al reported Fmocdipeptide and used in catalytic role as thermolysin. 34 In another study did by Gazit et al coassembly of Fmoc diphenylalanine and diphenylalanine form the 3D fibers viscous network. 35 Our group is interested in studying the self-assembly of single amino acid, 12,25,36,37 modified single amino acids, 20,29,30 peptides, [38][39][40][41][42][43] and heterocyclic compounds.…”

Polyaniline Functionalized Peptide Self-Assembled Conductive Hydrogel for 3D Cell Culture

“…These peptides have been reported to self-assemble into nanoparticles [ 13 , 14 ], nanotubes [ 15 ], nanobelts [ 16 ], nanofibers [ 17 ] and so on. The inherent sensitivity of peptides to pH, temperature, ions and enzymes provides these self-assembled architectures with good controllability and biological intelligence responsiveness [ 18 , 19 , 20 , 21 ]. Furthermore, functional groups could be dopped into peptide assembled architectures to endow them with new functions.…”