Armadillidin: a novel glycine-rich antibacterial peptide directed against gram-positive bacteria in the woodlouse Armadillidium vulgare (Terrestrial Isopod, Crustacean).
We report the isolation and the characterization of a novel antibacterial peptide from hemocytes of the woodlouse Armadillidium vulgare, naturally infected or uninfected by Wolbachia, an intracellular Gram-negative bacterium. This molecule displays antibacterial activity against Gram-positive bacteria despite its composition which classes it into the glycine-rich antibacterial peptide family, usually directed against fungi and Gram-negative bacteria. The complete sequence was determined by a combination of Edman degradation, mass spectrometry and cDNA cloning using a hemocyte library. The mature peptide (53 residues) has a 5259 Da molecular mass and is post-translationally modified by a C-terminal amidation. This peptide is characterized by a high level of glycine (47%) and a fivefold repeated motif GGGFH(R/S). As no evident sequence homology to other hitherto described antibacterial peptides has been found out, this antibacterial peptide was named armadillidin. Armadillidin is constitutively expressed in hemocytes and appears to be specific of A. vulgare.
Herbinière
Juline
J
Laboratoire de Génétique et Biologie des Populations de Crustacés, Unité mixte de Recherche 6556, CNRS, Université de Poitiers, 40 avenue du Recteur Pineau, 86022 Poitiers, France.
Braquart-Varnier
Christine
C
Grève
Pierre
P
Strub
Jean-Marc
JM
Frère
Jacques
J
Van Dorsselaer
Alain
A
Martin
Gilbert
G
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001483:Base Sequence; D015152:Blotting, Northern; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000254:growth & development; D016908:Gram-Positive Bacterial Infections / Q000378:metabolism; D006434:Hemocytes / Q000378:metabolism; D033321:Isopoda / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010455:Peptides; D012313:RNA / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000900:Anti-Bacterial Agents; D010455:Peptides; D012313:RNA