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Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
Structural glance into a novel anti-staphylococcal peptide
N B Iannucci1, L M Curto, F Albericio
1Department of Biological Chemistry and Institute of Biochemistry and Biophysics (IQUIFIB), School of Pharmacy and Biochemistry, University of Buenos Aires, Junín 956, C1113AAD, Buenos Aires, Argentina; Therapeutic Peptides Research and Development Laboratory, Chemo-Romikin, Carlos Villate 5148, B1605AXL, Buenos Aires, Argentina.
Biopolymers
|August 29, 2013
Summary
Researchers developed a novel antimicrobial peptide from human lysozyme with enhanced anti-staphylococcal activity. Its structural changes improve bacterial membrane interaction, aiding in combating drug-resistant bacteria.
Area of Science:
- Biochemistry
- Microbiology
- Drug Discovery
Background:
- Antimicrobial peptides (AMPs) are crucial for combating rising microbial drug resistance.
- Human lysozyme fragment 107-115 serves as a basis for novel antimicrobial agents.
Purpose of the Study:
- To investigate a novel peptide derived from human lysozyme (RKWVWWRNR-NH2) for enhanced anti-staphylococcal activity.
- To elucidate the structural and functional relationship between peptide conformation and bacterial membrane interaction.
Main Methods:
- Circular dichroism and fluorescence spectroscopy were used for conformational analysis.
- Interaction with model lipidic phases was studied to assess membrane binding.
- Site-directed mutagenesis (Ala to Trp substitution) was employed to study structural impact.
Main Results:
- The novel peptide (RKWVWWRNR-NH2) exhibited a 20-fold increase in anti-staphylococcal activity.
- Conformational analysis revealed significant spectral changes upon interaction with lipidic phases.
- A single amino acid substitution (Trp at position 111) dramatically altered peptide secondary structure and enhanced membrane interaction.
Conclusions:
- Peptide secondary structure and residue distribution are critical for effective bacterial membrane interaction.
- Enhanced interaction with the bacterial plasma membrane is linked to the peptide's lethal effect.
- This study provides insights for the rational design of next-generation antimicrobial peptides from natural sources.
Keywords:
cationic antimicrobial peptidescircular dichroismconformationfluorescencehuman lysozymephospholipid detergent micellesMore Related Videos
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