Diversified Carbohydrate-Binding Lectins from Marine Resources

Abstract

Marine bioresources produce a great variety of specific and potent bioactive molecules including natural organic compounds such as fatty acids, polysaccharides, polyether, peptides, proteins, and enzymes. Lectins are also one of the promising candidates for useful therapeutic agents because they can recognize the specific carbohydrate structures such as proteoglycans, glycoproteins, and glycolipids, resulting in the regulation of various cells via glycoconjugates and their physiological and pathological phenomenon through the host-pathogen interactions and cell-cell communications. Here, we review the multiple lectins from marine resources including fishes and sea invertebrate in terms of their structure-activity relationships and molecular evolution. Especially, we focus on the unique structural properties and molecular evolution of C-type lectins, galectin, F-type lectin, and rhamnose-binding lectin families.

A Lectin from the Mussel Mytilus galloprovincialis Has a Highly Novel Primary Structure and Induces Glycan-mediated Cytotoxicity of Globotriaosylceramide-expressing Lymphoma Cells

“…In analogy, the primary structure of D-galactoside-binding lectin isolated from SUEL had no structural homologues when we first reported it in 1991 (11); however, Ͼ1000 structural homologues with SUELtype lectin domains have been found during the 20 years since then. This structure has been observed even in the lectin domain of a neurotoxin receptor (latrophilin-1) in mammalian brain (52,53) and in plant ␤-galactosidase (54). As an example of a new structural domain in animal lectins, MytiLec is of interest in and will promote the field of glycobiology.…”

Evolution and Immune Function of Fish Lectins

“…Fish RBLs increase their expression in response to inflammatory stimuli, enhance phagocytosis acting as opsonins, and induce the synthesis and release of proinflammatory cytokines. 21,36,40,46 The ability to recognize and bind lipopolysaccharides and lipoteichoic acid and agglutinate both gram-positive and gram-negative bacteria has been described in trout RBLs, suggesting an antibacterial activity. 22,35,44,47 In addition, RBLs have also been found in the cortex of teleost eggs as well as in the skin mucus and serum, further confirming their protective role.…”

“…1 RBLs are Ca 2+ -independent lectins with specificity for rhamnose and galactosides, particularly abundant in teleosts and aquatic invertebrate species, such as annelids, bivalves, and ascidians. 36,37 RBLs share the presence of one or multiple CRDs with a unique β/β fold, about 100 amino acid in length, with 8 highly conserved cysteine residues engaged in 4 disulfide bridges with characteristic topology. 22,38,39 In addition, conserved motifs (YGR, DPC, and KYL) are also found.…”

“…According to Ogawa et al, 36 animal RBL CRDs were clustered into seven groups. The composite CRD structure of RBLs allowed the identification of 13 types of RBL genes.…”

“…The ligand of fish RBL is the glycosphingolipid globotriaosylceramide (Gb3), which is abundant in membrane lipid rafts. 17,21,36 The RBL CRD appeared early in metazoan evolution and it is found in a variety of proteins, with different domain architecture, To protect the rights of the author(s) and publisher we inform you that this PDF is an uncorrected proof for internal business use only by the author(s), editor(s), reviewer(s), Elsevier and typesetter TNQ Books and Journals Pvt Ltd. It is not allowed to publish this proof online or in print.…”