Research published in Peptides explains how differences observed between L-tryptophan and D-tryptophan containing the contryphan-Ar1131 peptide — in terms of oxidative folding, trypsin binding and photostabilization activity on avobenzone — inspired the synthesis of two reduced forms contryphan-Ar1131 (W5 and w5), whose properties were explored in greater depth.
The optimized structures of the reduced peptides revealed the occurrence of aromatic-aromatic and aromatic-proline interactions, in the case of w5, that could reportedly be critical in aiding the oxidative folding reaction. Competitive binding studies and molecular docking, along with molecular dynamic simulations, revealed w5 also had more affinity for the active site of trypsin.
The photostabilization activity of W5 and w5 on avobenzone under natural sunlight also was investigated. The latter had better photostabilization activity than that of W5 and also individual D-tryptophan and L-tryptophan amino acids. The authors suggest these insights could find applications in cosmetics.