Medicinal and Pharmaceutical Chemistry Commons^™

Broad-Spectrum Activity Of Membranolytic Cationic Macrocyclic Peptides Against Multi-Drug Resistant Bacteria And Fungi, Sandeep Lohan, Anastasia G. Konshina, Rakesh K. Tiwari, Roman G. Efremov, Innokentiy Maslennikov, Keykavous Parang

Pharmacy Faculty Articles and Research

The emergence of multidrug-resistant (MDR) strains causes severe problems in the treatment of microbial infections owing to limited treatment options. Antimicrobial peptides (AMPs) are drawing considerable attention as promising antibiotic alternative candidates to combat MDR bacterial and fungal infections. Herein, we present a series of small amphiphilic membrane-active cyclic peptides composed, in part, of various nongenetically encoded hydrophilic and hydrophobic amino acids. Notably, lead cyclic peptides 3b and 4b showed broad-spectrum activity against drug-resistant Gram-positive (MIC = 1.5–6.2 µg/mL) and Gram-negative (MIC = 12.5–25 µg/mL) bacteria, and fungi (MIC = 3.1–12.5 µg/mL). Furthermore, lead peptides displayed substantial antibiofilm action comparable …

Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Tools And Antimicrobial Agents, David Salehi

Pharmaceutical Sciences (MS) Theses

Cell-penetrating peptides containing arginine as positively charged residues and tryptophan or diphenylalanine as hydrophobic residues were synthesized. The synthesis was accomplished through the Fmoc solid-phase peptide synthesis in the presence of HBTU and DIPEA. The side-chain protected linear peptides were cleaved from the resin and cyclized in the presence of DIC and HOAt in the solution phase overnight. MALDI-TOF mass spectrometry was used to characterize the peptides.

The cytotoxicity of the synthesized peptides was determined in CCRF-CEM (human, lymphoblast peripheral blood), and HEK-293 (human, embryonic epithelial kidney healthy) cells using the MTS assay. A concentration of 10 µM was found …