Derivatives of the antimicrobial peptide BP100 for expression in plant systems

PLoS One. 2013 Dec 23;8(12):e85515. doi: 10.1371/journal.pone.0085515. eCollection 2013.

Abstract

Production of antimicrobial peptides in plants constitutes an approach for obtaining them in high amounts. However, their heterologous expression in a practical and efficient manner demands some structural requirements such as a minimum size, the incorporation of retention signals to assure their accumulation in specific tissues, and the presence of protease cleavage amino acids and of target sequences to facilitate peptide detection. Since any sequence modification may influence the biological activity, peptides that will be obtained from the expression must be screened prior to the synthesis of the genes for plant transformation. We report herein a strategy for the modification of the antimicrobial undecapeptide BP100 that allowed the identification of analogues that can be expressed in plants and exhibit optimum biological properties. We prepared 40 analogues obtained by incorporating repeated units of the antimicrobial undecapeptide, fragments of natural peptides, one or two AGPA hinges, a Gly or Ser residue at the N-terminus, and a KDEL fragment and/or the epitope tag54 at the C-terminus. Their antimicrobial, hemolytic and phytotoxic activities, and protease susceptibility were evaluated. Best sequences contained a magainin fragment linked to the antimicrobial undecapeptide through an AGPA hinge. Moreover, since the presence of a KDEL unit or of tag54 did not influence significantly the biological activity, these moieties can be introduced when designing compounds to be retained in the endoplasmic reticulum and detected using a complementary epitope. These findings may contribute to the design of peptides to be expressed in plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antimicrobial Cationic Peptides / biosynthesis*
  • Genetic Engineering / methods*
  • Oligopeptides / genetics*
  • Oligopeptides / metabolism*
  • Plants / genetics*
  • Plants, Genetically Modified
  • Transformation, Genetic / genetics*

Substances

  • Antimicrobial Cationic Peptides
  • Oligopeptides
  • lysyl-lysyl-leucyl-phenylalanyl-lysyl-lysyl-isoleucyl-leucyl-lysyl-tyrosyl-leucinamide

Grant support

This work was supported by grants AGL2006-13564/AGR, AGL2009-13255-C02-02/AGR, and ERA-NET PLANT-KBBE Euroinvestigación EUI2008-03572 from MICINN of Spain. The LIPPSO and CIDSAV groups are recognized as 2009SGR182 and 2009SGR182 by the Catalonian Government. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.