© 2006 The Japanese Biochemical Society.
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Comparative Biochemical Study of N-Linked Glycans from Skin of a Squid, Todarodes pacificus
1 Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043; and 2Department of Applied Biology, Kyoto Institute of Technology, Sakyo, Kyoto 606-8585
* To whom correspondence should be addressed at: Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043. Tel: +81-6-6850-5381, Fax: +81-6-6850-5382, E-mail: skawa{at}ktmail.ktokai-u.ac.jp
For comparative biochemical interest, we analyzed the structures of N-glycans in a squid belonging to the Lophotrochozoa, one of the protostome clades. N-Glycans were prepared from squid skin by hydrazinolysis and re-N-acetylation followed by fluorescent tagging with 2-aminopyridine. The labeled N-glycans were purified, and their structures were determined by the two-dimensional HPLC mapping method combined with glycosidase digestions and mass spectrometry. We found that high mannose-type glycans, paucimannose-type glycans and complex-type glycans with a type-1 structure (Galß1-3GlcNAc) were dominant in squid skin. The complex-type glycans detected in the squid were similar to those in vertebrates, but have not yet been found in the Ecdysozoa, which is another protostome clade. However, paucimannose-type glycans are commonly found in the Ecdysozoa. Thus, the N-glycan structures of the squid belonging to the Lophotrochozoa have features common to those in vertebrates and the Ecdysozoa including insects and nematodes.