Primary structure and opsonic activity of an F-lectin from serum of the gilt head bream Sparus aurata (Pisces, Sparidae)

Abstract

The recently described fucose-binding agglutinin from the European eel revealed a novel lectin fold (the 'F-type' fold) that is shared with other carbohydrate-binding proteins and proteins from prokaryotes to vertebrates clustered under the newly established F-type lectin (FTL) family. We previously reported the purification and biochemical characterization of a fucose-binding protein (FBP) isolated from serum of the gilt head bream (Sparus aurata, SauFBP). In the present article, the complete coding sequence of SauFBP revealed that it is a member of the FTL family, consisting of two tandem carbohydrate recognition domains (CRD) that display the F-type sequence motif. In vitro opsonization assays showed that the isolated SauFBP binds to formalin-killed Escherichia coli and enhances their phagocytosis by peritoneal macrophages. © Copyright 2012 Unione Zoologica Italiana.