title: Ctenidins: antimicrobial glycine-rich peptides from the hemocytes of the spider Cupiennius salei.
abstract: Three novel glycine-rich peptides, named ctenidin 1-3, with activity against the Gram-negative bacterium E. coli, were isolated and characterized from hemocytes of the spider Cupiennius salei. Ctenidins have a high glycine content (>70%), similarly to other glycine-rich peptides, the acanthoscurrins, from another spider, Acanthoscurria gomesiana. A combination of mass spectrometry, Edman degradation, and cDNA cloning revealed the presence of three isoforms of ctenidin, at least two of them originating from simple, intronless genes. The full-length sequences of the ctenidins consist of a 19 amino acid residues signal peptide followed by the mature peptides of 109, 119, or 120 amino acid residues. The mature peptides are post-translationally modified by the cleavage of one or two C-terminal cationic amino acid residue(s) and amidation of the newly created mature C-terminus. Tissue expression analysis revealed that ctenidins are constitutively expressed in hemocytes and to a small extent also in the subesophageal nerve mass.
authors.affiliation: Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland.
authors.forename: Tommy
authors.initials: T
authors.lastname: Baumann
authors.forename: Urs
authors.initials: U
authors.lastname: Kämpfer
authors.forename: Stefan
authors.initials: S
authors.lastname: Schürch
authors.forename: Johann
authors.initials: J
authors.lastname: Schaller
authors.forename: Carlo
authors.initials: C
authors.lastname: Largiadèr
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Nentwig
authors.forename: Lucia
authors.initials: L
authors.lastname: Kuhn-Nentwig
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000032:analysis / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D017931:DNA Primers; D005260:Female; D005998:Glycine / Q000032:analysis; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006434:Hemocytes / Q000378:metabolism*; D010455:Peptides / Q000276:immunology / Q000302:isolation & purification / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D021241:Spectrometry, Mass, Electrospray Ionization; D013112:Spiders / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology / Q000378:metabolism
chemical_list: D000596:Amino Acids; D023181:Antimicrobial Cationic Peptides; D017931:DNA Primers; D010455:Peptides; C415987:gomesin; D005998:Glycine