Antimicrobial Activity of Silver Nanoparticles Loaded Biomimetic Isomeric Short Lipopeptide Nanostructures

Abstract

Lipopeptide‐inspired lipidation of two short tripeptides, Phe‐Tyr‐β‐Ala and Tyr‐Phe‐β‐Ala leads to a pair of constitutional isomers of short peptide amphiphile (sPA). These two molecules were able to mimic lipopeptides properties and therefore could be used as potential drug delivery vehicles up to target sites. Further, these isomeric peptide amphiphiles were able to synthesize stable silver nanoparticles (AgNPs) in presence of sunlight without using any reducing agents. Interestingly, the presence of AgNPs significantly controls the secondary structures of these two isomeric sPAs and hence their self‐assembly. Therefore, such AgNPs‐sPA nanostructures are further used to develop antibacterial materials. Various microscopy and spectroscopy techniques were used to characterize these nanostructures. The antibacterial analysis demonstrated that owing to high biocompatibility and less cytotoxicity, designed sPA exhibited great potential in locally addressing bacterial infections. Thus, such a strategic design of lipidated tripeptide fragments can be tuned for potential therapeutic value for future applications.

Silver‐Nanoparticle‐Embedded Short Amphiphilic Peptide Nanostructures and Their Plausible Application to Reduce Bacterial Infections

“…Therefore a new strategy for predicting the degree of stability of sPA structures was used by studying its secondary structural properties. Three variants of short peptide amphiphiles were further synthesized by the insertion of a tyrosine residue at the appropriate position [16] . It is otherwise stated that the selective hydroxylation (Tyr‐insertion) of Phe1 and Phe2 moiety in sPA lead to sPA2 and sPA3 respectively.…”

“…It is otherwise stated that the selective hydroxylation (Tyr‐insertion) of Phe1 and Phe2 moiety in sPA lead to sPA2 and sPA3 respectively. Studies have shown that all three hydroxylated (sPA2 and sPA3) and their non‐hydroxylated (sPA) sPAs have high biocompatibility with the bacterial cell membrane [17,18] and the potential to synthesize Ag/AuNPs, therefore, were used to develop antibacterial materials [13,16,19] . Accordingly given our emerging interest, this time too we have developed a new variant of sPA by replacing both Phe1 and Phe2 with Tyr (Scheme 1).…”

“…The biologically relevant AgNPs formulated with sPA1 nanostructures lead to unique and facile hybrid nanosystems. Our previous well‐documented research work demonstrates that such an AgNPs−peptide hybrid system, owing to its lipophilic properties can easily target microbial membranes without any side effects [16] . Cell toxicity assay against healthy Vero cells by using MTT assay was performed.…”

“…Three variants of short peptide amphiphiles were further synthesized by the insertion of a tyrosine residue at the appropriate position. [16] It is otherwise stated that the selective hydroxylation (Tyr-insertion) of Phe1 and Phe2 moiety in sPA lead to sPA2 and sPA3 respectively. Studies have shown that all three hydroxylated (sPA2 and sPA3) and their non-hydroxylated (sPA) sPAs have high biocompatibility with the bacterial cell membrane [17,18] and the potential to synthesize Ag/AuNPs, therefore, were used to develop antibacterial materials.…”

“…Studies have shown that all three hydroxylated (sPA2 and sPA3) and their non-hydroxylated (sPA) sPAs have high biocompatibility with the bacterial cell membrane [17,18] and the potential to synthesize Ag/AuNPs, therefore, were used to develop antibacterial materials. [13,16,19] Accordingly given our emerging interest, this time too we have developed a new variant of sPA by replacing both Phe1 and Phe2 with Tyr (Scheme 1). [19,15] Alternatively, one can say that a simple hydroxylation (Tyr-insertion) of both Phe1 and Phe2 moiety can be obtained by using Mammalian/ bacterial phenylalanine hydroxylase (PAH) that catalyzes phenylalanine into tyrosine thus may stop the production of phenylketonuria (PKU) and lethal hyperphenylalaninemia.…”