Study On Enhancing Intracellular Bactericidal Effect And Biofilm Dispersing Effect By Self-assembly Of Peptides

In this work,two new antibacterial drugs were successfully prepared by peptide solid-phase synthesis method,in light of the current state of bacterial resistance research and some problems in drug application: polypeptide polymer(RK21)with antibacterial peptide(RK9)as prodrug and NO supply Body-shaped polypeptide polymer(LE-6),and used in intracellular sterilization and biofilm dispersal,respectively.Characteristics techniques including Circular dichroism spectroscopy(CD),dynamic light scattering particle size analysis(DLS),Fourier transform infrared spectroscopy(FTIR),and Transmission electron microscopy(TEM)were used to characterize the structure and morphology of the synthesized peptide nanomaterials.Then,the biosafety and antibacterial properties of drug materials were studied.The RK21 demonstrated superior intracellular bacteria eradication effect together with efficient cell entry,which proved that RK21 have ability in delaying intracellular bacteria drug resistance.The polypeptide polymer assembly RK15 has a lower minimum inhibitory concentration(18 M)than the pure antimicrobial peptide RK9(28M).The therapeutic molecule LE-6 connected with NO donor shows excellent bactericidal effect towards grown pseudomonas aeruginosa biofilm,LE-6 can reduce the total bacterial biofilm from 100% to roughly 50% when it is subjected to tetrazinemediated bioorthogonal shearing.The resultant peptide compound RK21 and LE-6 with NO donor connected demonstrated superior intracellular bacteria removal effect and bacterial biofilm dispersal effect.In summary,this work provides a new strategy for infection treatment caused by intracellular bacteria and bacterial biofilms.