Purification and characterization of antimicrobial peptides from the skin secretions of the carpenter frog Rana virgatipes (Ranidae, Aquarana)

J. Michael Conlon, Bency Abraham, Agnes Sonnevend, Thierry Jouenne, Pascal Cosette, Jerome Leprince, Hubert Vaudry, Catherine R. Bevier

Research output: Contribution to journalArticlepeer-review

40 Citations (Scopus)

Abstract

The members of the Aquarana (or Rana catesbeiana species group) form a well-supported monophyletic clade but phylogenetic relationships between species within the group are incompletely understood. Peptides that differentially inhibited the growth of bacteria were purified from electrically stimulated skin secretions of the carpenter frog Rana virgatipes. Structural characterization identified members of the ranatuerin-2 (3 peptides) and temporin (3-peptides) families, previously found in the skins of R. catesbeiana, R. clamitans, R. grylio and R. septentrionalis. Ranalexin, a peptide previously found only in the Aquarana, was isolated together with a variant (FFGLHNLVPSMLCVVRKKC) that lacks the propensity to adopt an α-helical conformation and so was devoid of antimicrobial activity. Two C-terminally α-amidated peptides belonging to the brevinin-2 family were isolated from the skin secretions that, like an ortholog from R. septentrionalis, lacked the C-terminal cyclic heptapeptide domain associated with members of this family. Ranatuerin-1, previously isolated from R. catesbeiana, R. clamitans and R. grylio but absent from R. septentrionalis, was also not identified in R. virgatipes. Synthetic replicates of temporin-1Va (FLSSIGKILGNLL.NH2), temporin-IVb (FLSIIAKVLGSLF.NH2) and temporin-1Vc (FLPLVTMLLGKLF.NH2) potently inhibited growth of Gram-positive bacteria (including methicillin-resistant Staphylococcus aureus). Temporin-1Va was also active against Gram-negative bacteria and the opportunistic yeast pathogen Candida albicans and had relatively weak hemolytic activity (LD50 = 120 μM) and may therefore represent a candidate for drug development. Our data support the placement of R. virgatipes in the Aquarana and indicate a closer phylogenetic relationship of R. virgatipes with R. septentrionalis than with R. catesbeiana, R. clamitans and R. grylio.

Original languageEnglish
Pages (from-to)38-45
Number of pages8
JournalRegulatory Peptides
Volume131
Issue number1-3
DOIs
Publication statusPublished - Nov 15 2005
Externally publishedYes

Keywords

  • Antimicrobial peptide
  • Brevinin-2
  • Frog skin
  • Ranalexin
  • Ranatuerin-2
  • Temporin

ASJC Scopus subject areas

  • Biochemistry
  • Physiology
  • Endocrinology
  • Clinical Biochemistry
  • Cellular and Molecular Neuroscience

Fingerprint

Dive into the research topics of 'Purification and characterization of antimicrobial peptides from the skin secretions of the carpenter frog Rana virgatipes (Ranidae, Aquarana)'. Together they form a unique fingerprint.

Cite this