PepSAVI-MS Reveals a Proline-rich Antimicrobial Peptide in Amaranthus tricolor
peer-reviewed · Journal of Natural Products · 2019
| Date | 2019-10-25 |
| Type | peer-reviewed |
| Venue | Journal of Natural Products |
| Publisher | American Chemical Society (ACS) |
| Contribution | downstream-application |
| DOI | 10.1021/acs.jnatprod.9b00352 |
| Citations (OpenAlex) | 29 |
Abstract
Traditional medicinal plants are a rich source of antimicrobials; however, the bioactive peptide constituents of most ethnobotanical species remain largely unexplored. Herein, PepSAVI-MS, a mass spectrometry-based peptidomics pipeline, was implemented for antimicrobial peptide (AMP) discovery in the medicinal plant Amaranthus tricolor . This investigation revealed a novel 1.7 kDa AMP with strong activity against Escherichia coli ATCC 25922, deemed Atr-AMP1. Initial efforts to determine the sequence of Atr-AMP1 utilized chemical derivatization and enzymatic digestion to provide information about specific residues and post-translational modifications. EThcD (electron-transfer/higher-energy collision dissociation) produced extensive backbone fragmentation and facilitated de novo sequencing, the results of which were consistent with orthogonal characterization experiments. Additionally, multistage HCD (higher-energy collisional dissociation) facilitated discrimination between isobaric leucine and isoleucine. These results revealed a positively charged proline-rich peptide present in a heterogeneous population of multiple peptidoforms, possessing several post-translational modifications including a disulfide bond, methionine oxidation, and proline hydroxylation. Additional bioactivity screening of a simplified fraction containing Atr-AMP1 revealed activity against Staphylococcus aureus LAC, demonstrating activity against both a Gram-negative and a Gram-positive bacterial species unlike many known short chain proline-rich antimicrobial peptides.
Methods and tools
- PepSAVI-MS Amaranthus tricolor antimicrobial peptide: PepSAVI-MS discovered the novel proline-rich antimicrobial peptide Atr-AMP1, whose sequence was determined by EThcD-enabled de novo sequencing with multistage HCD to tell leucine from isoleucine.
Methods it uses
- PEAKS: Commercial DP-based de novo
Data deposited
- PepSAVI-MS reveals proline-rich antimicrobial peptide in Amaranthus tricolor — as deposited · PXD014547