title: Linear antimicrobial peptides from Ectatomma quadridens ant venom.
abstract: Venoms from three poneromorph ant species (Paraponera clavata, Ectatomma quadridens and Ectatomma tuberculatum) were investigated for the growth inhibition of Gram-positive and Gram-negative bacteria. It was shown that the venom of E. quadridens and its peptide fraction in particular possess marked antibacterial action. Three linear antimicrobial peptides sharing low similarity to the well-known ponericin peptides were isolated from this ant venom by means of size-exclusion and reversed-phase chromatography. The peptides showed antimicrobial activity at low micromolar concentrations. Their primary structure was established by direct Edman sequencing in combination with mass spectrometry. The most active peptide designated ponericin-Q42 was chemically synthesized. Its secondary structure was investigated in aqueous and membrane-mimicking environment, and the peptide was shown to be partially helical already in water, which is unusual for short linear peptides. Analysis of its activity on different bacterial strains, human erythrocytes and chronic myelogenous leukemia K562 cells revealed that the peptide shows broad spectrum cytolytic activity at micromolar and submicromolar concentrations. Ponericin-Q42 also possesses weak toxic activity on flesh fly larvae with LD50 of ∼105 μg/g.
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
authors.forename: Kirill A
authors.initials: KA
authors.lastname: Pluzhnikov
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia. Electronic address: serg@ibch.ru.
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Kozlov
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Vassilevski
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
authors.forename: Olga V
authors.initials: OV
authors.lastname: Vorontsova
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
authors.forename: Alexei V
authors.initials: AV
authors.lastname: Feofanov
authors.affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya, 16/10, 117997 Moscow, Russia.
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Grishin
mesh_terms: D000595:Amino Acid Sequence; D000862:Ant Venoms / Q000737:chemistry* / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000494:pharmacology; D002942:Circular Dichroism; D004353:Drug Evaluation, Preclinical / Q000379:methods; D006801:Humans; D020014:K562 Cells / Q000187:drug effects; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D017433:Protein Structure, Secondary
chemical_list: D000862:Ant Venoms; D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D010455:Peptides; C000599868:ponericin-Q42, Ectatomma quadridens
keywords: Ant venom; Antimicrobial peptide; Cytolytic peptide; Insect toxin