New l-Rhamnose-Binding Lectin from the Bivalve IGlycymeris yessoensis/I: Purification, Partial Structural Characterization and Antibacterial Activity

• Published in: Marine drugs Vol. 22; no. 1
• Main Authors: Mizgina, Tatyana O, Chikalovets, Irina V, Bulanova, Tatyana A, Molchanova, Valentina I, Filshtein, Alina P, Ziganshin, Rustam H, Rogozhin, Eugene A, Shilova, Nadezhda V, Chernikov, Oleg V
• Format: Journal Article
• Language: English
• Published: MDPI AG 01-12-2023
• Subjects: Antibacterial agents; Biological products; Bivalvia; Chemical properties; Health aspects; Identification and classification; Lectins; Pharmaceutical research; Russia
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md22010027

In this study, a new l-rhamnose-binding lectin (GYL-R) from the hemolymph of bivalve Glycymeris yessoensis was purified using affinity and ion-exchange chromatography and functionally characterized. Lectin antimicrobial activity was examined in different ways. The lectin was inhibited by saccharides possessing the same configuration of hydroxyl groups at C-2 and C-4, such as l-rhamnose, d-galactose, lactose, l-arabinose and raffinose. Using the glycan microarray approach, natural carbohydrate ligands were established for GYL-R as l-Rha and glycans containing the α-Gal residue in the terminal position. The GYL-R molecular mass determined by MALDI-TOF mass spectrometry was 30,415 Da. The hemagglutination activity of the lectin was not affected by metal ions. The lectin was stable up to 75 °C and between pH 4.0 and 12.0. The amino acid sequence of the five GYL-R segments was obtained with nano-ESI MS/MS and contained both YGR and DPC-peptide motifs which are conserved in most of the l-rhamnose-binding lectin carbohydrate recognition domains. Circular dichroism confirmed that GYL is a α/β-protein with a predominance of the random coil. Furthermore, GYL-R was able to bind and suppress the growth of the Gram-negative bacteria E. coli by recognizing lipopolysaccharides. Together, these results suggest that GYL-R is a new member of the RBL family which participates in the self-defense mechanism against bacteria and pathogens with a distinct carbohydrate-binding specificity.