beta1,3-N-Acetylglucosaminyltransferase-7 (beta3Gn-T7) acts efficiently on keratan sulfate-related glycans.
beta1,3-N-Acetylglucosaminyltransferase-7 (beta3Gn-T7) has been identified as an anti-migration factor for a lung cancer cell line but its enzymatic activity has not yet been characterized. Here we show that beta3Gn-T7 efficiently acts on keratan sulfate-related glycans including Galbeta1-->4(SO(3)(-)-->6)GlcNAcbeta1-->3Galbeta1-->4(SO(3)(-)-->6)GlcNAc (L2L2), while lacto-N-tetraose and lacto-N-neo-tetraose were poor substrates. Moreover, we found that among the other five beta3Gn-Ts and i antigen-producing beta3Gn-T (iGn-T), beta3Gn-T2 and iGn-T act well on L2L2, although these specific activities were lower than those for a tetraantennary N-glycan. These results indicate that beta3Gn-T7 is the one that most efficiently elongates L2L2 and may be involved in the biosynthesis of keratan sulfate.
Seko
Akira
A
Department of Biochemistry, Sasaki Institute, 2-2, Kanda-Surugadai, Chiyoda-ku, 101-0062, Tokyo, Japan.
Yamashita
Katsuko
K
D002240:Carbohydrate Sequence; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D007632:Keratan Sulfate / Q000031:analogs & derivatives* / Q000096:biosynthesis; D007700:Kinetics; D008969:Molecular Sequence Data; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics / Q000378:metabolism*; D009844:Oligosaccharides / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity; D014316:Tritium
D007527:Isoenzymes; D009844:Oligosaccharides; D011134:Polysaccharides; D011994:Recombinant Proteins; D014316:Tritium; D007632:Keratan Sulfate; D017351:N-Acetylglucosaminyltransferases