Table 2.
Known glycosyltransferase complexes, their functions, species identified and references
| Function | Organism | References | |
|---|---|---|---|
| Heteromeric enzyme complexes | |||
| Lactose synthase (LS, GalT-I/α-lactalbumin) | Lactose synthesis | H. sapiens | [4–8] |
| Alg7p/Alg13p/Alg14p | Synthesis of man-dolichol precursor | S. cerevisiae | [16] |
| Alg1/Alg2/Alg11 | Synthesis of man-dolichol precursor | S. cerevisiae | [18] |
| Oligosaccharyltransferase complex (OST) | Glycan precursor transfer to the acceptor | S. cerevisiae | [20–24] |
| M-Pol I [Van1p/Mnn9p] | Early mannosyl addition in the Golgi | S. cerevisiae | [29] |
| M-Pol II [Hoc1p/Mnn11p/Mnn10p/Anp1p/Mnn9p] | Late mannosyl addition in the Golgi | S. cerevisiae | [29] |
| Pmt2p/Pmt3p, Pmt1p/Pmt2p, Pmt5p/Pmt3p | Initiation of O-mannosyl glycans | S. cerevisiae | [58] |
| GlcNAcT-I/GlcNAcT-II | N-glycan branching | H. sapiens | [35, 40, 41] |
| GalT-I/ST6Gal-I and GalT-I/ST3Gal-III | Termination of N-glycans | H. sapiens | [40, 41] |
| B3GnT-8/B3GnT-2 | Synthesis of polylactosamine | H. sapiens | [44, 45] |
| TPST1/ST6Gal-I, TPST2/ST6Gal-I | Tyrosylprotein sulfation/sialylation | H. sapiens | [46] |
| GlcNAcT-I/GnT1IPL | Inhibition of N-glycan branching | M. musculus | [47] |
| GalNAcT-6/C1GalT-1, -/C3GnT-1, -/C2GnT-1 | Synthesis of O-glycan cores 1, 3 and 6 | H. sapiens | [41] |
| EXT1/EXT2, Epi/2OST | Heparan sulfate synthesis | H. sapiens, M. musculus | [72–74] |
| ChSy-1/ChSy-2, ChPF/CSGlcA-T | Chondroitin sulfate synthesis | H. sapiens | [75] |
| B4GalT6/SiaT9/SiaT8A, B4GalNT1/B3GalT4 | Synthesis of ganglio-series GSLs | H. sapiens | [68–70] |
| SiaT8A/B4GALNT1 | Synthesis of ganglio-series GSLs | H. sapiens | [67] |
| HAS1/HAS2, HAS1/HAS3, HAS2/HAS3 | Hyalyronan synthesis | H. sapiens | [76] |
| POMT1/POMT2 | O-mannosylation | H. sapiens | [56, 57] |
| CESA1/CESA2/CESA3/CESA6 | Primary cell wall synthesis | A. thaliana | [87] |
| CESA4/CESA7/CESA8 | Secondary cell wall synthesis | A. thaliana | [ [87] |
| Chs3p/Chs4p | Chitin synthesis | S. cerevisiae | [77] |
| GALT-1/GMII | Plant N-glycan branching | A. thaliana | [48, 49] |
| GAUT1/GAUT7 | Homogalacturonan synthesis | A. thaliana | [85] |
| XXT2/XXT5, XXT1/XXT2, XXT5/CSLC4 | Xyloglucan backbone synthesis | A. thaliana | [92] |
| SSI/SSIIa/SBEIIa or SBEIIb | Starch synthesis and branching | T. aestivum/Z. mays | [93, 94] |
| SP/SBEI, SP/SBEIIb | Starch branching and degradation | Z. mays | [95] |
| Homomeric enzyme complexes | |||
| Pmt4p | Elongation of mannan | S. cerevisiae | [58] |
| GlcNAcT-I, GlcNAcT-II | N-glycan branching | H. sapiens | [35, 40, 41] |
| GlcNAcT-V | N-glycan branching | H. sapiens | [36] |
| FucT-I, FucT-III and FucT-VI | Modification of N-glycans | H. sapiens | [34, 38, 39] |
| GalT-I | Termination of N-glycans | H. sapiens | [30, 31, 39, 42] |
| ST6Gal-I | N-glycan termination | H. sapiens/R. norvegicus | [33, 37, 38] |
| C2GnT-1 | Core 6 synthetase | H. sapiens | [50] |
| C1GalT-1 | Core 1 synthetase | H. sapiens | [51, 52] |
| LH3 | O-Glycosylation of collagens | H. sapiens | [61, 62] |
| GlcAT-1 | GlcA transfer to proteoglycans | H. sapiens | [71] |
| B4GALNT1 and SiaT8a | Synthesis of ganglio-series GSLs | H. sapiens | [65, 66] |
| HAS2 and HAS3 | Hyalyronan synthesis | H. sapiens | [76] |
| CESA1 to CESA10 | Plant cell wall synthesis [cellulose] | A. thaliana | [84] |
| CHS-2 | Chitin synthesis [cell wall] | M. sexta | [78] |
| MNS1, GMII, GnTI and GnTII | N-glycan branching | A. thaliana/N. tabacum | [48, 49] |
| XylT | Xyloylation | A. thaliana | [48] |
| ARAD1 and ARAD2 | Synthesis of pectic arabinan | N. benthamiana | [90] |
| FUT1, CSLC4 and XXT1 to 5 | Xyloglucan backbone synthesis | A. thaliana | [91, 92] |
| MUR3 and XLT2 | Xyloglucan backbone synthesis | A. thaliana | [92] |
| SSI, SSIIa, and SBEIIa/b | Amylopectin synthesis and branching | T. aestivum/Z. mays | [93, 94] |