Title
Meristiella echinocarpa lectin (MEL): a new member of the OAAH-lectin family
Author
Renata Pinheiro Chaves, Suzete Roberta da Silva, João Pedro Freire Alves da Silva, Rômulo Farias Carneiro, Bruno Lopes de Sousa, Jade Oliveira Abreu, Fátima Cristiane Teles de Carvalho, Cintia Renata Costa Rocha, Wladimir Ronald Lobo Farias, Oscarina Viana de Sousa, André Luiz Coelho Silva, Alexandre Holanda Sampaio, Celso Shiniti Nagano
Year
2018
Journal
Journal of Applied Phycology
Abstract
A new lectin from the marine red alga Meristiella echinocarpa (MEL) was isolated and biochemically characterized. MEL is a monomeric protein of 28 kDa with specificity for yeast mannan. Hemagglutination activity of MEL was stable between pH 5 and 10, temperatures up to 50 °C, and neither EDTA nor divalent ions affected it. The complete amino acid sequence of MEL was determined through a combination of tandem mass spectrometry and DNA cloning. As a new member of the OAAH-lectin family, the primary structure of MEL consists of 267 amino acid residues distributed in four tandem repeat domains, sharing at least 48% of identity. Theoretical secondary structure of MEL was composed of 3% α-helix, 40% β-sheet, 19% β-turn, and 38% coil. Melting temperatures of the lectin in the absence and presence of mannan were 54 and 61 °C, respectively. Furthermore, MEL was able to recognize and agglutinate pathogenic bacterial strains, such as multidrug-resistant Salmonella and Vibrio alginolyticus.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Thermal stability, Thermodynamics, Biochemistry