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Molecular dynamics simulation is performed to investigate self-insertion behaviors of peptides into single-walled carbon nanotubes (SWCNTs) in water environment. Peptides of different hydrophobicities and varied lengths are tested to show that the propensities of peptides to self-insert into SWCNTs differ drastically. Our results indicate that there exists a potential well for the system of SWCNT and peptide that is able to self-insert into the nanotube. Further investigations of energy components demonstrate that electrostatic interactions, combined with van der Waals interactions, play dominant roles in the self-insertion of peptides into nanotubes. In addition, we also observe a significant correlation between the propensity of a peptide to insert into nanotube and its hydrophobicity. Such results provide valuable information on the potential applications of carbon nanotubes in the fields of drug delivery, drug design and protein control, etc.

Engineering the molecular assembly at biomolecular interface is one of the prevailing techniques in synthetic biology to derive novel supramolecular structures. In this study, we have biofunctionalized polyoxometalates with peptide-based cationic polymer. Surface functionalization of polyoxometalates (POMs) results in derivation of self-assembled polymer–POM nanocomposites with novel antifungal activity. Electron rich POM triggers the morphological alteration in molecularly enriched $\beta$-sheet peptide polymer promoting the evolution of nanorods. Due to the inherited biocidal properties of the cationic polymer and the POM, the nanorods exhibit enhanced antifungal activity highlighting the significance of combinatorial systems in advanced drug therapeutics.

Two new zinc(II)porphyrin oligopeptide conjugates (zinc(II)-5,10,15,20-bis[4-(peptide)- phenyl]porphyrin (5) and -tetrakis[3,5-di(peptide)phenyl]porphyrin (9; peptide = -CH₂(CO)Gly-Phe-Ala-CNH₂) were prepared using the click chemistry with azides and ethynyl-containing precursors. The spectroscopic signature (S₀→S₁ and transient T₁→T_n absorption, excitation and emission spectra) are typical for zinc(II)porphyrin and shows no perturbation upon anchoring the oligopeptides, whereas some small decreases in the photophysical parameters (𝜏_F and Φ_F), and larger decrease in T₁ lifetimes are noted, which are attributable to the known "loose bolt" effect. The structure for 9 in solution was addressed qualitatively using computer modeling and the comparison of the bimolecular fluorescence quenching rate constants between 5 and 9 using C₆₀ as a photooxidative agent. While 5 exhibits a totally accessible zinc(II)porphyrin unit for a C₆₀ approach, 9 shows a slower quenching rate constant meaning some steric hindrance must be present.

This paper proposes a new paradigm for the biophysical concept of measuring the affinity of molecular complexes, based on a matrix representation of biological interactions and subsequent numerical analysis of the stability of this matrix. Our numerical criterion of stability (lg(cond($W$))) correlates well with experimental values such as $K_d$ and IC${}_{50}$ as well as with experimental data of aggregation kinetics in studies of amyloid peptides. The main goal of this work is to reduce the cost of biochemical experiments by obtaining preliminary information on the interaction of chemical compounds. The paper also presents our numerical calculations in comparison with a large amount of experimental data on the examples of binding of small chemical molecules gefitinib, erlotinib, imatinib, naquatinib, and CO-1686 with proteins, protein–peptide interactions of the Bcl-2 protein family, antibody–antigen CD20–rituximab, and aggregation of amyloid peptides. The description of the software package that implements the presented algorithm is given on the website: https://binomlabs.com/.