Purification and characterization of antimicrobial peptides from the skin secretion of Rana dybowskii.
Six antimicrobial peptides designated dybowskins were isolated from the skin secretion of Rana dybowskii, an edible frog in Korea. Dybowskin-1 (FLIGMTHGLICLISRKC) and dybowskin-2 (FLIGMTQGLICLITRKC) were isoforms differing in only two amino acid residues at the 7th and 14th positions from the N-terminus, and they showed amino acid sequence similarities with ranalexin peptides. Dybowskin-3 (GLFDVVKGVLKGVGKNVAGSLLEQLKCKLSGGC), dybowskin-4 (VWPLGLVICKALKIC), dybowskin-5 (GLFSVVTGVLKAVGKNVAKNVGGSLLEQLKCKISGGC), and dybowskin-6 (FLPLLLAGLPLKLCFLFKKC) differed in both size and sequence, and they were, in terms of amino acid sequence similarities, related to brevinin-2, japonicin-2, esculentin-2, and brevinin-1 peptides, respectively. All the peptides presented in this paper contained Rana-box, the cyclic heptapeptide domain, which is conserved in other antimicrobial peptides derived from the genus Rana. All the dybowskin peptides showed a broad spectrum of antimicrobial activity against the Gram-positive and Gram-negative bacteria (minimum inhibition concentrations (MIC), 12.5 to >100 microg/ml) and against Candida albicans (MIC, 25 to >100 microg/ml). Especially, dybowskin-4 with valine at its N-terminus was the most abundant and showed the strongest antimicrobial activity among all the dybowskin peptides. This result indicates that the dybowskin peptides from R. dybowskii, whose main habitats are mountains or forests, have evolved differently from antimicrobial peptides isolated from other Korean frogs, whose habitats are plain fields.
Kim
Sukwon S
SS
Laboratory of Molecular Genetics and Genomics, School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, South Korea.
Shim
Myoung Sup
MS
Chung
Jiyeol
J
Lim
Doo-Yeon
DY
Lee
Byeong Jae
BJ
D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics / Q000302:isolation & purification* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011898:Ranidae / Q000235:genetics / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000378:metabolism
D023181:Antimicrobial Cationic Peptides