A family of brevinin-2 peptides with potent activity against Pseudomonas aeruginosa from the skin of the Hokkaido frog, Rana pirica.
Nine peptides displaying varying degrees of antimicrobial activity were extracted from the skin of the Hokkaido frog, Rana pirica. Five structurally related peptides were identified as members of the brevinin-2 family. These peptides were active against reference strains of Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae, Klebsiella pneumoniae) and Gram-positive (Staphlococcus aureus) bacteria but displayed relatively low hemolytic activity. The most abundant peptide, brevinin-2PRa (680 nmol/g weight of dry skin) showed high potency [minimal inhibitory concentration (MIC) values between 6 and 12 microM] against a range of clinical isolates of P. aeruginosa. In addition, activity was unaffected by NaCl concentrations up to 200 mM. Cladistic analysis based on the primary structures of brevinin-2 peptides supports a close phylogenetic relationship between R. pirica and Japanese mountain brown frog Rana ornativentris. One peptide of the ranatuerin-2 family and one strongly hemolytic peptide of the brevinin-1 family were also isolated from the extract along with two members of the temporin family, temporin-1PRa (ILPILGNLLNGLL.NH(2)) and temporin-1PRb (ILPILGNLLNSLL.NH(2)) that atypically lacked basic amino acid residues and showed only very weak antimicrobial and hemolytic activity.
Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, 17666 Al-Ain, United Arab Emirates. jmconlon@uaeu.ac.ae
J Michael
JM
Conlon
Agnes
A
Sonnevend
Mahrendra
M
Patel
Khawla
K
Al-Dhaheri
Per F
PF
Nielsen
Jolanta
J
Kolodziejek
Norbert
N
Nowotny
Shawichi
S
Iwamuro
Tibor
T
Pál
D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D024881:Drug Resistance, Bacterial; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010455:Peptides; D010802:Phylogeny; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D011898:Ranidae; D012867:Skin / Q000382:microbiology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D029845:Amphibian Proteins; D023181:Antimicrobial Cationic Peptides; D010455:Peptides; D011506:Proteins; C121230:ranatuerin; C104501:temporin; C078413:brevinin-1 protein, Rana; C078414:brevinin-2, Rana