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Updated: May 6, 2026

A Lectin HPLC Method to Enrich Selectively-glycosylated Peptides from Complex Biological Samples
Published on: October 1, 2009
H-3, a new lectin from the marine sponge Haliclona caerulea: purification and mass spectrometric characterization
Rômulo Farias Carneiro1, Arthur Alves de Melo, Alexandra Sampaio de Almeida
1Laboratório de Moléculas Biologicamente Ativas - BioMol-Lab, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Campus do Pici, s/n bloco 907, 60440-970 Fortaleza, Ceará, Brazil(1).
Abstract:
A new lectin from the marine sponge Haliclona caerulea (H-3) was isolated using a combination of hydrophobic interaction chromatography and ion-exchange chromatography. H-3 is a protein with three distinct bands on SDS-PAGE: 9 kDa, 16 kDa and 18 kDa. Nevertheless, on gel filtration and N-PAGE, H-3 showed a symmetrical peak and a unique band, respectively. Hemagglutinating activity of H-3 was stable at neutral pH and temperatures up to 60 °C. N-Acetylgalactosamine and porcine stomach mucin were the most potent inhibitors of H-3. Primary structure of the lectin was determined using tandem mass spectrometry, and it showed no similarity to any members of the animal lectin families. Top down fragmentation revealed some posttranslational modifications in H-3, including glycosylation. The glycan composition of H-3 was determined, and its structure was predicted. Furthermore, H-3 is a blue protein, binding to a chromophore(-597) by weak interactions, and this is the first time that the interaction between one lectin and a natural chromophore has been shown.

