Download MendeleyCrystal structure of a symbiosis-related lectin from octocoral.
Kita, A., Jimbo, M., Sakai, R., Morimoto, Y., Miki, K.(2015) Glycobiology 25: 1016-1023
- PubMed: 26022515
- DOI: https://doi.org/10.1093/glycob/cwv033
- Primary Citation of Related Structures:
3WMP, 3WMQ - PubMed Abstract:
D-Galactose-binding lectin from the octocoral, Sinularia lochmodes (SLL-2), distributes densely on the cell surface of microalgae, Symbiodinium sp., an endosymbiotic dinoflagellate of the coral, and is also shown to be a chemical cue that transforms dinoflagellate into a non-motile (coccoid) symbiotic state. SLL-2 binds with high affinity to the Forssman antigen (N-acetylgalactosamine(GalNAc)α1-3GalNAcβ1-3Galα1-4Galβ1-4Glc-ceramide), and the presence of Forssman antigen-like sugar on the surface of Symbiodinium CS-156 cells was previously confirmed. Here we report the crystal structures of SLL-2 and its GalNAc complex as the first crystal structures of a lectin involved in the symbiosis between coral and dinoflagellate. N-Linked sugar chains and a galactose derivative binding site common to H-type lectins were observed in each monomer of the hexameric SLL-2 crystal structure. In addition, unique sugar-binding site-like regions were identified at the top and bottom of the hexameric SLL-2 structure. These structural features suggest a possible binding mode between SLL-2 and Forssman antigen-like pentasaccharide.
Organizational Affiliation:
Research Reactor Institute, Kyoto University, Kumatori, Sennan, Osaka 590-0494, Japan kita@rri.kyoto-u.ac.jp miki@kuchem.kyoto-u.ac.jp.
