title: Identification and characterization of two novel antimicrobial peptides, temporin-Ra and temporin-Rb, from skin secretions of the marsh frog (Rana ridibunda).
abstract: In this study, two novel antimicrobial peptides from the skin secretions of the marsh frog, Rana ridibunda, named temporin-Ra and temporin-Rb, were identified and purified using RP-HPLC. Temporin-Ra and temporin-Rb are composed of 14 and 12 amino acids, respectively. Our results show that these peptides have inhibitory effects on both gram-negative and gram-positive bacteria, especially antibiotic resistant strains prevalent in hospitals, such as Staphylococcus aureus and Streptococcus agalactiae. The sequences and molecular weights of these peptides were determined using tandem MS. The molecular masses were found to be 1242.5 Da for temporin-Rb and 1585.1 Da for temporin-Ra. Human red blood cells tolerated well exposure to temporin-Ra and temporin-Rb, which, at a concentration of 60 µg/ml, induced 1.3% and 1.1% hemolysis, respectively. MIC values of these peptides are suitable for potent antimicrobial peptides. The low hemolytic effect and wide-spectrum antimicrobial activity suggest a possible therapeutic application of these novel peptides.
authors.affiliation: Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran. asoodeh@um.ac.ir
authors.forename: Ahmad
authors.initials: A
authors.lastname: Asoodeh
authors.forename: Hadi Zare
authors.initials: HZ
authors.lastname: Zardini
authors.forename: Jamshidkhan
authors.initials: J
authors.lastname: Chamani
mesh_terms: D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D024901:Drug Resistance, Multiple, Bacterial; D004912:Erythrocytes / Q000187:drug effects; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000254:growth & development; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000254:growth & development; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020033:Protein Isoforms / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011895:Rana ridibunda; D012867:Skin / Q000737:chemistry / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D029845:Amphibian Proteins; D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D020033:Protein Isoforms; D011506:Proteins; C104501:temporin