title: Identification and bioactivity evaluation of two novel temporins from the skin secretion of the European edible frog, Pelophylax kl. esculentus.
abstract: The amphibian temporins, amongst the smallest antimicrobial peptides (AMPs), are α-helical, amphipathic, hydrophobic and cationic and are active mainly against Gram-positive bacteria but inactive or weakly active against Gram-negative bacteria. Here, we report two novel members of the temporin family, named temporin-1Ee (FLPVIAGVLSKLFamide) and temporin-1Re (FLPGLLAGLLamide), whose biosynthetic precursor structures were deduced from clones obtained from skin secretion-derived cDNA libraries of the European edible frog, Pelophylax kl. esculentus, by 'shotgun' cloning. Deduction of the molecular masses of each mature processed peptide from respective cloned cDNAs was used to locate respective molecules in reverse-phase HPLC fractions of secretion. Temporin-1Ee (MIC = 10 μM) and temporin-1Re (MIC = 60 μM) were both found to be active against Gram-positive Staphylococcus aureus, but retaining a weak haemolytic activity. To our knowledge, Single-site substitutions can dramatically change the spectrum of activity of a given temporin. Compared with temporine-1Ec, just one chemically-conservative substitution (Val8 instead of Leu8), temporin-1Ee bearing a net charge of +2 displays broad-spectrum activity with particularly high potency on the clinically relevant Gram-negative strains, Escherichia coli (MIC = 40 μM). These factors bode well for translating temporins to be potential drug candidates for the design of new and valuable anti-infective agents.
authors.affiliation: School of Pharmacy, Fujian Medical University, Fuzhou, 350001, Fujian, China. Electronic address: leochen5139@fjmu.edu.cn.
authors.forename: Xiaole
authors.initials: X
authors.lastname: Chen
authors.affiliation: School of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, 350001, Fujian, China. Electronic address: hwang11@qub.ac.uk.
authors.forename: He
authors.initials: H
authors.lastname: Wang
authors.affiliation: Medicine Natural Peptide Discovery Group, School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Mu
authors.initials: M
authors.lastname: Yang
authors.affiliation: Medicine Natural Peptide Discovery Group, School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Medicine Natural Peptide Discovery Group, School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Mei
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Medicine Natural Peptide Discovery Group, School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Tianbao
authors.initials: T
authors.lastname: Chen
authors.affiliation: Medicine Natural Peptide Discovery Group, School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Shaw
mesh_terms: D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000235:genetics* / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000494:pharmacology / Q000502:physiology*; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D008826:Microbial Sensitivity Tests; D011506:Proteins / Q000235:genetics* / Q000494:pharmacology / Q000502:physiology*; D011898:Ranidae / Q000235:genetics* / Q000502:physiology*; D012867:Skin / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D029845:Amphibian Proteins; D023181:Antimicrobial Cationic Peptides; D018076:DNA, Complementary; D011506:Proteins; C104501:temporin
keywords: Amphibian; Antimicrobial peptide; Molecular cloning; Temporins