Designing Chimeric Peptides: A Powerful Tool for Enhancing Antibacterial Activity

Abstract

Chimeric peptides containing short sequences derived from bovine Lactoferricin (LfcinB) and Buforin II (BFII) were synthetized using solid‐phase peptide synthesis (SPPS) and characterized via reversed‐phase liquid chromatography and mass spectrometry. The chimeras were obtained with high purity, demonstrating their synthetic viability. The chimeras’ antibacterial activity against Gram‐positive and Gram‐negative strains was evaluated. Our results showed that all the chimeras exhibited greater antibacterial activity against the evaluated strains than the individual sequences, suggesting that chemical binding of short sequences derived from AMPs significantly increased the antibacterial activity. For each strain, the chimera with the best antibacterial activity exerted a bacteriostatic and/or bactericidal effect, which was dependent on the concentration. It was found that: (i) the antibacterial activity of a chimera is mainly influenced by the linked sequences, the palindromic motif RLLRRLLR being the most relevant one; (ii) the inclusion of a spacer between the short sequences did not significantly affect the chimera's synthesis process; however, it enhanced its antibacterial activity against Gram‐negative and Gram‐positive strains; on the other hand, (iii) the replacement of Arg with Lys in the LfcinB or BFII sequences improved the chimeras’ synthesis process without significantly affecting their antibacterial activity. These results illustrate the great importance of the synthesis of chimeric peptides for the generation of promising antibacterial peptides.

Designed Multifunctional Peptides for Intracellular Targets

“…The palindromic motifs RLLRRLLR and RWQWR enhance the antibacterial activity against Gram-negative and Gram-positive strains [ 243 ] when chimeric peptides are constructed based on buforin 2 sequence TRSSRAGLQFPVGRVH RLLR K [ 159 ] and lactoferricin fragment R RWQWR MKKLG [ 244 ]. Both buforin 2 and lactoferricin have confirmed strong antibacterial, anticancer, antifungal, anti-endotoxin, DNA-binding, and cell-penetrating properties (see [ 8 , 159 , 245 , 246 , 247 ] for validated activities of buforin-like peptides, and [ 248 , 249 , 250 , 251 ] for lactoferricin-like peptides).…”

Targeting Protein Interaction Hotspots Using Structured and Disordered Chimeric Peptide Inhibitors

“…Using both inhibitors at the same time can create a synergistic effect, and a covalent linkage between them may enable simultaneous binding with enhanced binding kinetics and affinity . To do so, new peptide-based inhibitors have been designed as chimeric peptides, which are composed of two (or more) peptides that have different targets or act under a specific mechanism of action. , Chimera design and synthesis is considered one of the most promising alternatives for identifying peptides with potent activity.…”

“…19 To do so, new peptide-based inhibitors have been designed as chimeric peptides, which are composed of two (or more) peptides that have different targets or act under a specific mechanism of action. 20,21 Chimera design and synthesis is considered one of the most promising alternatives for identifying peptides with potent activity.…”

Chimeric Peptides Derived from Bovine Lactoferricin and Buforin II: Antifungal Activity against Reference Strains and Clinical Isolates of Candida spp.

“…To overcome these limits and improve the antimicrobial activity, the native sequence of AMPs has been modified. Some of the optimization strategies of AMPs include reducing the amino acid chain, inserting non-natural amino acids, increasing the polyvalence of the sequence, and combining sequences of two or more AMPs (chimeras), among others [ 16 , 17 , 18 , 19 , 20 ]. LfcinB is a peptide fragment of 25 residues in length located in the N-terminal region of bovine lactoferrin (LfB) and is generated during hydrolysis of this protein with gastric pepsin [ 21 , 22 ].…”

“…The palindrome [RLLR] 5 : RLLRRLLRRLLRRLLRRLLR was reported to have an MIC of 0.7 µM against E. coli. Chimeras containing the minimum motif RRWQWR attached to RLLR or RLLRRRLLR showed greater antibacterial activity than individual sequences [ 18 , 20 , 27 , 28 , 29 , 30 ].…”