title: Identification and cloning of a glucan- and lipopolysaccharide-binding protein from Eisenia foetida earthworm involved in the activation of prophenoloxidase cascade.
abstract: Coelomic fluid of Eisenia foetida earthworms contains a 42-kDa protein named coelomic cytolytic factor 1 (CCF-1) that was described previously to be involved in cytolytic, opsonizing, and hemolytic properties of the coelomic fluid. Cloning and sequencing of CCF-1 reveal significant homology with the putative catalytic region of beta-1,3- and beta-1,3-1,4-glucanases. CCF-1 also displays homology with coagulation factor G from Limulus polyphemus and with Gram-negative bacteria-binding protein of Bombyx mori silkworm, two proteins involved in invertebrate defense mechanisms. We show that CCF-1 efficiently binds both beta-1,3-glucan and lipopolysaccharide. Moreover, CCF-1 participates in the activation of prophenoloxidase cascade via recognition of yeast and Gram-negative bacteria cell wall components. These results suggest that the 42-kDa CCF-1 protein of E. foetida coelomic fluid likely plays a role in the protection of earthworms against microbes.
authors.affiliation: Unit of Cellular Immunology, Flemish Interuniversity Institute for Biotechnology, VIB-VUB, Paardenstraat 65, B-1640 St-Genesius-Rode, Belgium. abeschin@vub.ac.be
authors.forename: A
authors.initials: A
authors.lastname: Beschin
authors.forename: M
authors.initials: M
authors.lastname: Bilej
authors.forename: F
authors.initials: F
authors.lastname: Hanssens
authors.forename: J
authors.initials: J
authors.lastname: Raymakers
authors.forename: E
authors.initials: E
authors.lastname: Van Dyck
authors.forename: H
authors.initials: H
authors.lastname: Revets
authors.forename: L
authors.initials: L
authors.lastname: Brys
authors.forename: J
authors.initials: J
authors.lastname: Gomez
authors.forename: P
authors.initials: P
authors.lastname: De Baetselier
authors.forename: M
authors.initials: M
authors.lastname: Timmermans
mesh_terms: D000209:Acute-Phase Proteins; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004156:Catechol Oxidase / Q000378:metabolism*; D003001:Cloning, Molecular; D003603:Cytotoxins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism*; D005936:Glucans / Q000378:metabolism; D005959:Glucosidases / Q000737:chemistry; D007700:Kinetics; D037102:Lectins; D008070:Lipopolysaccharides / Q000378:metabolism / Q000494:pharmacology; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D009835:Oligochaeta / Q000235:genetics / Q000502:physiology*; D011134:Polysaccharides / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D000099231:Lipopolysaccharide-Binding Protein
chemical_list: D000209:Acute-Phase Proteins; D002352:Carrier Proteins; D004156:Catechol Oxidase; D003603:Cytotoxins; D004792:Enzyme Precursors; D005936:Glucans; D005959:Glucosidases; D037102:Lectins; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D011134:Polysaccharides; D011994:Recombinant Proteins; D000099231:Lipopolysaccharide-Binding Protein; C094795:coelomic cytolytic factor 1, Eisenia fetida; C037937:glucan-binding proteins; C008247:laminaran; C038451:pro-phenoloxidase