title: Cm38: a new antimicrobial peptide active against Klebsiella pneumoniae is homologous to Cn11.
abstract: Antimicrobial peptides (AMPs) represent a large and ubiquitous group of peptides. The current crisis in antibiotic therapy has led to an intensified search for new antimicrobial agents. In this regard, scorpion venom constitutes a rich source of biologically active peptides including AMPs. In the present study, the purification of a novel peptide with antimicrobial activity against the Gram-negative bacteria Klebsiella pneumoniae is described. This antimicrobial peptide, named Cm38, was purified from Centruroides margaritatus scorpion venom using a two-step chromatographic strategy using C8 and C18 columns. This toxin inhibits the proliferation of the Gram-negative bacteria Klebsiella pneumoniae with a Minimal Inhibitory Concentration (MIC) of 64 μM. An analysis of the N-terminal sequence of Cm38 revealed a close structural relationship to Cn11, a Na+-channel modulator toxin previously isolated from Centruroides noxius scorpion venom. Therefore, to test Cm38 for effects on ion channels, we measured its effects on action potential firing in cultured dorsal root ganglion neurons. Cm38 depolarized and increased action potential firing in a subset of neurons tested. The present work reports a new peptide related to Cn11 with antimicrobial properties that is also active in neurons.
authors: R A
authors: RA
authors: Dueñas-Cuellar
authors: C
authors: C
authors: Kushmerick
authors: L A
authors: LA
authors: Naves
authors: I F C
authors: IF
authors: Batista
authors: J A
authors: JA
authors: Guerrero-Vargas
authors: O R
authors: OR
authors: Pires
authors: Wagner
authors: W
authors: Fontes
authors: Toxinology Laboratory, Department of Physiological Sciences, Institute of Biology, University of Brasilia, Brasilia/DF, Brazil. mscastro@unb.br.
authors: Mariana S
authors: MS
authors: Castro
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004594:Electrophysiology; D005727:Ganglia, Spinal / Q000166:cytology / Q000187:drug effects*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects*; D008297:Male; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009474:Neurons / Q000166:cytology / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D012604:Scorpion Venoms / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D012604:Scorpion Venoms; C460224:toxin 11, Centruroides noxius