title: Clavanins, alpha-helical antimicrobial peptides from tunicate hemocytes.
abstract: Hemocytes from the invertebrate Styela clava, a solitary tunicate, contained a family of four alpha-helical antimicrobial peptides that were purified, sequenced and named clavanins A, B, C and D. Each clavanin contained 23 amino acid residues and was C-terminally amidated. The tunicate peptides resembled magainins in size, primary sequence and antibacterial activity. Synthetic clavanin A was prepared and displayed comparable antimicrobial activity to magainins and cecropins. The presence of alpha-helical antimicrobial peptides in the hemocytes of a urochordate suggests that such peptides are primeval effectors of innate immunity in the vertebrate lineage.
authors.affiliation: Section of Molecular Host Defense, Department of Medicine, UCLA School of Medicine, Los Angeles, CA 90095-1690, USA.
authors.forename: I H
authors.initials: IH
authors.lastname: Lee
authors.forename: C
authors.initials: C
authors.lastname: Zhao
authors.forename: Y
authors.initials: Y
authors.lastname: Cho
authors.forename: S S
authors.initials: SS
authors.lastname: Harwig
authors.forename: E L
authors.initials: EL
authors.lastname: Cooper
authors.forename: R I
authors.initials: RI
authors.lastname: Lehrer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001798:Blood Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D006434:Hemocytes / Q000276:immunology*; D008089:Listeria monocytogenes / Q000187:drug effects; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D014561:Urochordata / Q000276:immunology*
chemical_list: D000900:Anti-Bacterial Agents; D001798:Blood Proteins; D010446:Peptide Fragments