Antimicrobial peptides from the skins of North American frogs

Biochim Biophys Acta. 2009 Aug;1788(8):1556-63. doi: 10.1016/j.bbamem.2008.09.018. Epub 2008 Oct 17.


North America is home to anuran species belonging to the families Bufonidae, Eleutherodactylidae, Hylidae, Leiopelmatidae, Ranidae, and Scaphiopodidae but antimicrobial peptides have been identified only in skin secretions and/or skin extracts of frogs belonging to the Leiopelmatidae ("tailed frogs") and Ranidae ("true frogs"). Eight structurally-related cationic alpha-helical peptides with broad-spectrum antibacterial activity, termed ascaphins, have been isolated from specimens of Ascaphus truei (Leiopelmatidae) occupying a coastal range. Characterization of orthologous antimicrobial peptides from Ascaphus specimens occupying an inland range supports the proposal that this population should be regarded as a separate species A. montanus. Ascaphin-8 shows potential for development into a therapeutically valuable anti-infective agent. Peptides belonging to the brevinin-1, esculentin-1, esculentin-2, palustrin-1, palustrin-2, ranacyclin, ranatuerin-1, ranatuerin-2, and temporin families have been isolated from North American ranids. It is proposed that "ranalexins" represent brevinin-1 peptides that have undergone a four amino acid residue internal deletion. Current taxonomic recommendations divide North American frogs from the family Ranidae into two genera: Lithobates and Rana. Cladistic analysis based upon the amino acid sequences of the brevinin-1 peptides provides strong support for this assignment.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Amphibian Proteins / isolation & purification*
  • Amphibian Proteins / pharmacology
  • Animals
  • Anti-Infective Agents / isolation & purification*
  • Anti-Infective Agents / pharmacology
  • Antimicrobial Cationic Peptides / isolation & purification*
  • Antimicrobial Cationic Peptides / pharmacology
  • Molecular Sequence Data
  • Proteins / isolation & purification
  • Proteins / pharmacology
  • Ranidae / classification
  • Ranidae / metabolism*
  • Skin / chemistry*


  • Amphibian Proteins
  • Anti-Infective Agents
  • Antimicrobial Cationic Peptides
  • Proteins
  • temporin
  • brevinin-1 protein, Rana
  • brevinin-2, Rana