Anti-TYR (aa 20-340) polyclonal antibody

This article reports enzyme-instructed self-assembly (EISA) of stereoisomers of pentapeptides as a simple approach for generating biocompatible supramolecular hydrogels as potential soft bionanomaterials. Peptide-based supramolecular hydrogels are emerging as a new type of biomaterials. The use of tyrosine phosphate offers a trigger for enzymatic hydrogelation, and the incorporation of D-amino acids can increase the proteolytic stability of peptides. This work compared four phosphorpeptides that are stereoisomers in terms of rate of dephosphorylation, proteolytic stability, and cell compatibility. The results show that the naphthyl (Nap)-capped pentapeptides, containing the amino acid sequence of Phe-Phe-Gly-Glu-(p)Tyr, are able to undergo EISA to form the hydrogels consisting the nanofibres of the dephosphorylated pentapeptides. The naphthyl-capped D-phosphopentpeptides, contrasting to a naphthyl-capped D-phosphotripeptide (Nap-D-Phe-D-Phe-D-(p)Tyr), are largely cell compatible. This result, suggesting that the sequence of phophopeptides also dedicates the cell compatibility of the peptide assemblies resulted from EISA, provides useful insights for developing supramolecular hydrogels as potential biomaterials with tailored properties.

This study systematically investigated the binding mechanism between capsaicin (CAP) and beta-lactoglobulin (beta-lg) through the method of multi-spectroscopic, thermodynamics, molecular docking, and molecular dynamics simulation at pH 7.4. The results showed that CAP could interact with beta-lg to enhance the fluorescence intensity of beta-lg. Simultaneously, the complex formed by CAP and beta-lg enhanced the hydrophobicity of the microenvironment of Trp and Tyr in beta-lg. The change in particle size without changing the secondary structure of beta-lg indicates a transition between the large aggregate particle to small aggregate particle of beta-lg. Isothermal titration calorimetric (ITC) results show that hydrophobic interactions play an important role in the formation of the complex. The MD simulation results showed that the RMSD of the systems reached equilibrium and wiggle around the mean value after 30 ns of simulation time. Analysis of Rg indicated that beta-lg and beta-lg/CAP complex was stabilized around 30 ns. Secondary structure analysis results showed that CAP has no distinct effect on the beta-lg structure. Furthermore, the van der Waals interactions are also involved in binding between beta-lg and CAP according to the result of MD simulation. The calculational results indicated that CAP preferred to bind to the hydrophobic pocket of beta-lg. The obtained results could provide some new clues to the interaction mechanism of beta-lg and CAP, which proved that beta-lg possesses the ability to apply in functional food as the vehicle of capsaicin.