Antimicrobial peptides derived from pepsinogens in the stomach of the bullfrog, Rana catesbeiana.
Three antimicrobial peptides, which had strong antimicrobial activity against a broad spectrum of microorganisms, were isolated from the stomach of the bullfrog, Rana catesbeiana. Two of the antimicrobial peptides were found to be derived from the N-terminal sequences of pepsinogen A and C prosequences. The amino acid sequences of the new antimicrobial peptides, named bullfrog pepsinogen A-derived antimicrobial peptide (bPaAP) and bullfrog pepsinogen C-derived antimicrobial peptide (bPcAP), were Gly-Val-Val-Lys-Val-Ser-Arg-Leu-Lys-Gly-Glu-Ser-Leu-Arg-Ala-Arg-Leu (MW 1865.5) and Ile-Ile-Lys-Val-Pro-Leu-Lys-Lys-Phe-Lys-Ser-Met-Arg-Glu-Val-Met-Arg-A sp-His-Gly-Ile-Lys-Ala-Pro-Val-Val-Asp-Pro-Ala-Thr-Lys-Tyr (MW 3691.6), respectively. The bPaAP and bPcAP adopted 35% and 42% amphipathic alpha-helical structure in 50% trifluoroethanol, respectively, and were non-hemolytic up to a concentration of 200 microg/ml. Synthesized pepsinogen C prosequences of monkey and human, which had similar structural characteristics as bPaAP and bPcAP, also showed antimicrobial activity at concentrations of 10-200 microg/ml. The third peptide was buforin I, previously found in the stomach of the Asian toad, Bufo bufo gargarizans. These findings strongly suggest that peptides derived from the prosequences of pepsinogens, along with buforin I, may contribute to the antimicrobial function of the gastrointestinal mucosa of vertebrates, including human.
Minn
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Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Yusong-gu, Kusong-dong, Taejon 305-701, South Korea.
Kim
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Kim
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D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D002942:Circular Dichroism; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020116:Pepsinogen A; D020115:Pepsinogen C; D010435:Pepsinogens / Q000302:isolation & purification / Q000494:pharmacology*; D010446:Peptide Fragments / Q000302:isolation & purification / Q000494:pharmacology*; D017433:Protein Structure, Secondary; D011506:Proteins / Q000494:pharmacology; D011892:Rana catesbeiana; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013270:Stomach / Q000737:chemistry*
D000890:Anti-Infective Agents; D010435:Pepsinogens; D010446:Peptide Fragments; D011506:Proteins; C113559:bPaAP peptide; C113560:bPcAP peptide; C097846:buforin I; D020115:Pepsinogen C; D020116:Pepsinogen A