title: Halocyntin and papillosin, two new antimicrobial peptides isolated from hemocytes of the solitary tunicate, Halocynthia papillosa.
abstract: We report here the screening of five marine invertebrate species from two taxa (tunicates and echinoderms) for the presence of cationic antimicrobial peptides (AMP) in defence cells (hemocytes). Antimicrobial activities were detected only in the two tunicates Microcosmus sabatieri and Halocynthia papillosa. In addition, we report the isolation and characterization of two novel peptides from H. papillosa hemocytes. These molecules display antibacterial activity against Gram-positive and Gram-negative bacteria. Complete peptide characterization was obtained by a combination of Edman degradation and mass spectrometry. The mature molecules, named halocyntin and papillosin, comprise 26 and 34 amino acid residues, respectively. Their primary structure display no significant similarities with previously described AMP.
authors.affiliation: Laboratoire de Biologie et d'Ecologie Tropicale et Méditerranéenne, CNRS-UPVD-EPHE, Perpignan, France. richard.galinier@univ-perp.fr
authors.forename: Richard
authors.initials: R
authors.lastname: Galinier
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Roger
authors.forename: Pierre-Eric
authors.initials: PE
authors.lastname: Sautiere
authors.forename: Andre
authors.initials: A
authors.lastname: Aumelas
authors.forename: Bernard
authors.initials: B
authors.lastname: Banaigs
authors.forename: Guillaume
authors.initials: G
authors.lastname: Mitta
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002942:Circular Dichroism; D004912:Erythrocytes / Q000187:drug effects; D006434:Hemocytes / Q000737:chemistry*; D050296:Microbial Viability / Q000187:drug effects; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D012756:Sheep; D014561:Urochordata / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D010455:Peptides; C541503:halocyntin protein, Halocynthia papillosa; C541504:papillosin protein, Halocynthia papillosa