Abstract
CEL-III is a Ca(2+)-dependent lectin purified from a sea cucumber, Cucumaria echinata. This protein exhibits strong hemolytic activity as well as cytotoxicity toward some cultured cell lines. Hemolysis is caused by CEL-III oligomers formed in the cell membrane after binding to specific carbohydrate chains on the cell surface. We have found that the oligomerization of CEL-III is also induced by the binding of simple carbohydrates, such as lactose, in aqueous solution under high pH and high ionic strength conditions. From gel filtration analysis of the oligomerization of CEL-III, it was found that the formation of the CEL-III oligomer is effectively induced by the binding of lactose and lactulose, disaccharides containing a beta-galactoside structure. Electron micrographs of the resulting oligomers revealed them to exist as particles with a size of approximately 20-30 nm. The oligomerization process required more than 1 h, which is consistent with the increase in surface hydrophobicity as measured using a fluorescent probe, 8-anilinonaphthalene-1-sulfonate. However, a change in the far-UV CD spectra as well as small-angle X-ray scattering occurred within a few minutes, suggesting that a structural change in the protein takes place rapidly, but the following growth of the oligomer is a much slower process.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.