Alpha-2,8-sialyltransferase 8B (EC 2.4.99.-) (Sialyltransferase 8B) (SIAT8-B) (Sialyltransferase St8Sia II) (ST8SiaII) (Sialyltransferase X) (STX)
1_MQLQF 6_ RSWML 11_ AALTL 16_ LVVFL 21_ IFADI 26_ SEIEE 31_ EIGNS 36_ GGRGT 41_ IRSAV 46_ NSLHS 51_ KSNRA 56_ EVVIN 61_ GSSSP 66_ AVVDR 71_ SNESI 76_ KHNIQ 81_ PASSK 86_ WRHNQ 91_ TLSLR 96_ IRKQI 101_ LKFLD 106_ AEKDI 111_ SVLKG 116_ TLKPG 121_ DIIHY 126_ IFDRD 131_ STMNV 136_ SQNLY 141_ ELLPR 146_ TSPLK 151_ NKHFG 156_ TCAIV 161_ GNSGV 166_ LLNSG 171_ CGQEI 176_ DAHSF 181_ VIRCN 186_ LAPVQ 191_ EYARD 196_ VGLKT 201_ DLVTM 206_ NPSVI 211_ QRAFE 216_ DLVNA 221_ TWREK 226_ LLQRL 231_ HSLNG 236_ SILWI 241_ PAFMA 246_ RGGKE 251_ RVEWV 256_ NELIL 261_ KHHVN 266_ VRTAY 271_ PSLRL 276_ LHAVR 281_ GYWLT 286_ NKVHI 291_ KRPTT 296_ GLLMY 301_ TLATR 306_ FCKQI 311_ YLYGF 316_ WPFPL 321_ DQNQN 326_ PVKYH 331_ YYDSL 336_ KYGYT 341_ SQASP 346_ HTMPL 351_ EFKAL 356_ KSLHE 361_ QGALK 366_LTVGQ
1: Catalyzes the transfer of a sialic acid from a CMP-linked sialic acid donor onto a terminal alpha-2,3-, alpha-2,6-, or alpha-2,8-linked sialic acid of an N-linked glycan acceptor through alpha-2,8-linkages (Probable) (PubMed:10766765, PubMed:11744634, PubMed:9054414, PubMed:9774483). Therefore, participates in polysialic acid synthesis on various sialylated N-acetyllactosaminyl oligosaccharides (alpha-2,3-, alpha-2,6-, or alpha-2,8-linked sialic acid), including NCAM1, NCAM1 N-glycans, FETUB N-glycans, and to a lesser extent sialylparagloboside (SPG) and AHSG, which does not require the initial addition of an alpha 2,8-sialic acid (Probable) (PubMed:7559389). However, does not exhibit sialic acid-polymerase activity (By similarity). Catalyzes polysialic acid synthesis in the hippocampal on NCAM1 and supports neurite outgrowth (PubMed:9054414). ST8SIA2-mediated polysialylation influences on oligodendrocyte differentiation and may promote the integrity of myelin and axons (By similarity)