An enhancer peptide for membrane-disrupting antimicrobial peptides.

Background: NP4P is a synthetic peptide derived from a natural, non-antimicrobial peptide fragment (pro-region of nematode cecropin P4) by substitution of all acidic amino acid residues with amides (i.e., Glu --> Gln, and Asp --> Asn).

Anionic C-terminal proregion of nematode antimicrobial peptide cecropin P4 precursor inhibits antimicrobial activity of the mature peptide.

Recently, an anionic proregion was found to be conserved at the C terminus of the antimicrobial peptide, nematode cecropin. Our results suggest that the antimicrobial activity of mature peptide is suppressed by the proregion in its precursor and is released from inhibition after processing. Inhibition is not likely to be due to direct suppression of membrane disruption.