Evidence of a bactericidal permeability increasing protein in an invertebrate, the Crassostrea gigas Cg-BPI.
A cDNA sequence with homologies to members of the LPS-binding protein and bactericidal/permeability-increasing protein (BPI) family was identified in the oyster Crassostrea gigas. The recombinant protein was found to bind LPS, to display bactericidal activity against Escherichia coli, and to increase the permeability of the bacterial cytoplasmic membrane. This indicated that it is a BPI rather than an LPS-binding protein. By in situ hybridization, the expression of the C. gigas BPI (Cg-bpi) was found to be induced in hemocytes after oyster bacterial challenge and to be constitutive in various epithelia of unchallenged oysters. Thus, Cg-bpi transcripts were detected in the epithelial cells of tissues/organs in contact with the external environment (mantle, gills, digestive tract, digestive gland diverticula, and gonad follicles). Therefore, Cg-BPI, whose expression profile and biological properties are reminiscent of mammalian BPIs, may provide a first line of defense against potential bacterial invasion. To our knowledge, this is the first characterization of a BPI in an invertebrate.
Gonzalez
Marcelo
M
Ifremer, Centre National de la Recherche Scientifique, Université Montpellier 2, Unité Mixte de Recherche 5119, Ecosystèmes Lagunaires, Place E. Bataillon, CC80, 34095 Montpellier Cedex 5, France.
Gueguen
Yannick
Y
Destoumieux-Garzón
Delphine
D
Romestand
Bernard
B
Fievet
Julie
J
Pugnière
Martine
M
Roquet
Françoise
F
Escoubas
Jean-Michel
JM
Vandenbulcke
Franck
F
Levy
Ofer
O
Sauné
Laure
L
Bulet
Philippe
P
Bachère
Evelyne
E
D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D001798:Blood Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002463:Cell Membrane Permeability; D049896:Crassostrea / Q000382:microbiology / Q000502:physiology*; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli / Q000502:physiology*; D020224:Expressed Sequence Tags; D007448:Invertebrates / Q000382:microbiology / Q000502:physiology; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010125:Ostreidae / Q000235:genetics / Q000382:microbiology / Q000502:physiology; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D018076:DNA, Complementary; D008565:Membrane Proteins; C021623:bactericidal permeability increasing protein