SYNTHESIS, CHARACTERIZATION AND STUDY OF THE ANTIMICROBIAL POTENTIAL OF PEPTIDES ANALOGUES TO PEPTIDE (p-BthTX-I)2

Microbial resistance to conventionally used antimicrobials is a global public health problem. The increasing prevalence of multidrug-resistant bacteria has led to the need for the discovery of new molecules to replace conventional antimicrobials. Antimicrobial peptides (AMPs) are promising alternatives, offering several advantages such as broad-spectrum activity, high specificity, and low induction of microbial resistance. The main objectives of this study are the synthesis of analog molecules to the peptide (p-BthTX-I)K2, namely p-MtII, p-EM-2, p-ACL, p-AppK, and the evaluation of the activity of the synthetic peptides against microorganisms, including multidrug-resistant strains. Peptide synthesis was performed using solid-phase peptide synthesis technique. The peptides were obtained with high purity (>95%). The molecules were named GB2203, GB2207, GB2211, and GB2214. All synthesized peptides demonstrated activity against bacterial strains, especially peptides GB2211 and GB2214, which showed bactericidal or bacteriostatic activity against all tested strains, including the P. aeruginosa strain for which no activity was observed by peptides GB2203 and GB2207. The modifications made to the peptide (p-BthTX-I)K2 were found to be replicable in all synthesized peptides during this study, resulting in antimicrobial activity against various tested bacterial strains, both gram-positive and gram-negative strains.