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Updated: Jun 1, 2026
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Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
Two antimicrobial and nematicidal peptides derived from sequences encoded Picea sitchensis
1Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Jiangsu, China.
Summary
Two novel antimicrobial peptides from Picea sitchensis, piceain 1 and 2, show potent activity against bacteria, fungi, and nematodes. These peptides possess a unique disulfide loop and low hemolytic activity.
Area of Science:
- Biochemistry
- Molecular Biology
- Natural Product Chemistry
Background:
- Antimicrobial peptides (AMPs) are crucial in innate immunity.
- Plant-derived AMPs offer potential for novel therapeutic agents.
- Picea sitchensis is a potential source of bioactive compounds.
Purpose of the Study:
- To identify and characterize novel antimicrobial peptides from Picea sitchensis.
- To evaluate the antimicrobial, nematicidal, and hemolytic activities of these peptides.
- To investigate the structural properties of the identified peptides.
Main Methods:
- Peptide synthesis based on identified sequences.
- Antimicrobial activity assays against various microorganisms (bacteria, fungi).
- Nematicidal assays against Caenorhabditis elegans.
- Hemolysis assays using human and rabbit red blood cells.
- Circular dichroism spectroscopy for structural analysis.
Main Results:
- Two peptides, piceain 1 and 2, were identified and synthesized.
- Piceain 1 and 2 exhibited antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans, with limited activity against Bacillus subtilis.
- Strong nematicidal activity against Caenorhabditis elegans was observed at low concentrations (10 µg/ml).
- Both peptides showed weak hemolytic activity (<5% at 250 µg/ml).
- Circular dichroism indicated a secondary structure rich in β-sheet and random coil.
Conclusions:
- Picea sitchensis encodes a novel family of antimicrobial and nematicidal peptides (piceains).
- These peptides feature a unique nine-amino acid disulfide loop.
- Piceains demonstrate broad-spectrum antimicrobial and nematicidal potential with low toxicity.
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