Yeast-Binding Lectin with Antibacterial Activity from Scapharca broughtonii

A mannose-specific lectin (SBL) with molecular mass of 29 kDa was isolated from the sea clam Scapharca broughtonii by chromatography on DEAE-52 and Sephadex G-100. SBL showed agglutination activity against yeast (Saccharomyces serevisiae) and antibacterial activity to bacteria, Escherichia coli, Shewanella sp. and Staphyloccocus aureus. The effects of SBL to bacteria NOS were investigated by Griess regent. Results showed that SBL exhibited promotion effect on the NO production of E. coli and Staphyloccocus aureus, and inhibition effect on the NO production of Shewanella sp. Bacterial nitric oxide synthases (NOS) produce NO by catalyzing the oxidation of arginine. NO mediated cell resistance to antibiotics. SBL did not show NO-mediated antibiotic resistance for Shewanella sp.. Supported by Natural Science Foundation of China (31071612) and Natural Science Foundation of China (21075012).