Innate immunity. Isolation of several cysteine-rich antimicrobial peptides from the blood of a mollusc, Mytilus edulis.
We have isolated from the blood of immune-challenged and untreated mussels (Mytilus edulis) antibacterial and antifungal peptides. We have characterized two isoforms of a novel 34-residue, cysteine-rich, peptide with potent bactericidal activity and partially characterized a novel 6.2-kDa antifungal peptide containing 12 cysteines. We report the presence of two members of the insect defensin family of antibacterial peptides and provide a phylogenetic analysis that indicates that mollusc and arthropod defensins have a common ancestry. Our data argue that circulating antimicrobial peptides represent an ancient host defense mechanism that predated the separation between molluscs and arthropods at the root of the Cambrian, about 545 million years ago.
Charlet
M
M
Unité Propre de Recherche 9022 Réponse Immunitaire et Développement chez les Insectes, CNRS, Institut de Biologie Moléculaire et Cellulaire, Strasbourg Cedex, France.
Chernysh
S
S
Philippe
H
H
Hetru
C
C
Hoffmann
J A
JA
Bulet
P
P
D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D049872:Bivalvia / Q000737:chemistry*; D001798:Blood Proteins / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003545:Cysteine; D023082:Defensins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
D000890:Anti-Infective Agents; D000935:Antifungal Agents; D001798:Blood Proteins; D023082:Defensins; D003545:Cysteine