9.B.142 The Integral membrane Glycosyltransferase family 39 (GT39) Family

Thousands of homologues of the GT39 family are found in bacteria, archaea and eukaryotes.  These integral membrane proteins function in glycosyl transfer, but some such enzymes have been shown to transport their substrates across the membrane in which they reside.  See TC families 4.D.1 and 4.D.2. These proteins may be distantly related to those in the GT39 family, TC# 9.B.142.  Protein N-glycosylation in an Asgard archaeon, now called Promethearchaeum syntrophicum, has been characterized (Nakagawa et al. 2024).



This family belongs to the Glycosyl/Acyl Transferase (GAT) Superfamily.

 

References:

Abu-Qarn, M., S. Yurist-Doutsch, A. Giordano, A. Trauner, H.R. Morris, P. Hitchen, O. Medalia, A. Dell, and J. Eichler. (2007). Haloferax volcanii AglB and AglD are involved in N-glycosylation of the S-layer glycoprotein and proper assembly of the surface layer. J. Mol. Biol. 374: 1224-1236.

Bai, L., A. Kovach, Q. You, A. Kenny, and H. Li. (2019). Structure of the eukaryotic protein O-mannosyltransferase Pmt1-Pmt2 complex. Nat Struct Mol Biol 26: 704-711.

Belardinelli, J.M. and M. Jackson. (2017). Green Fluorescent Protein as a protein localization and topological reporter in mycobacteria. Tuberculosis (Edinb) 105: 13-17.

Cohen-Rosenzweig, C., Z. Guan, B. Shaanan, and J. Eichler. (2014). Substrate promiscuity: AglB, the archaeal oligosaccharyltransferase, can process a variety of lipid-linked glycans. Appl. Environ. Microbiol. 80: 486-496.

Hug, L.A., B.J. Baker, K. Anantharaman, C.T. Brown, A.J. Probst, C.J. Castelle, C.N. Butterfield, A.W. Hernsdorf, Y. Amano, K. Ise, Y. Suzuki, N. Dudek, D.A. Relman, K.M. Finstad, R. Amundson, B.C. Thomas, and J.F. Banfield. (2016). A new view of the tree of life. Nat Microbiol 1: 16048.

Li, M., S.M. Aye, M.U. Ahmed, M.L. Han, C. Li, J. Song, J.D. Boyce, D.R. Powell, M.A.K. Azad, T. Velkov, Y. Zhu, and J. Li. (2020). Pan-transcriptomic analysis identified common differentially expressed genes of Acinetobacter baumannii in response to polymyxin treatments. Mol Omics 16: 327-338.

Lizak, C., S. Gerber, S. Numao, M. Aebi, and K.P. Locher. (2011). X-ray structure of a bacterial oligosaccharyltransferase. Nature 474: 350-355.

Morita, Y.S., C.B. Sena, R.F. Waller, K. Kurokawa, M.F. Sernee, F. Nakatani, R.E. Haites, H. Billman-Jacobe, M.J. McConville, Y. Maeda, and T. Kinoshita. (2006). PimE is a polyprenol-phosphate-mannose-dependent mannosyltransferase that transfers the fifth mannose of phosphatidylinositol mannoside in mycobacteria. J. Biol. Chem. 281: 25143-25155.

Nakagawa, S., H. Imachi, S. Shimamura, S. Yanaka, H. Yagi, M. Yagi-Utsumi, H. Sakai, S. Kato, M. Ohkuma, K. Kato, and K. Takai. (2024). Characterization of protein glycosylation in an Asgard archaeon. BBA Adv 6: 100118.

Ramírez, A.S., J. Kowal, and K.P. Locher. (2019). Cryo-electron microscopy structures of human oligosaccharyltransferase complexes OST-A and OST-B. Science 366: 1372-1375.

Ruiz-Canada, C., D.J. Kelleher, and R. Gilmore. (2009). Cotranslational and posttranslational N-glycosylation of polypeptides by distinct mammalian OST isoforms. Cell 136: 272-283.

Tavares-Carreón, F., K.B. Patel, and M.A. Valvano. (2015). Burkholderia cenocepacia and Salmonella enterica ArnT proteins that transfer 4-amino-4-deoxy-l-arabinose to lipopolysaccharide share membrane topology and functional amino acids. Sci Rep 5: 10773.

Tavares-Carreón, F., Y. Fathy Mohamed, A. Andrade, and M.A. Valvano. (2015). ArnT proteins that catalyse the glycosylation of lipopolysaccharide share common features with bacterial N-oligosaccharyltransferases. Glycobiology. [Epub: Ahead of Print]

Wild, R., J. Kowal, J. Eyring, E.M. Ngwa, M. Aebi, and K.P. Locher. (2018). Structure of the yeast oligosaccharyltransferase complex gives insight into eukaryotic N-glycosylation. Science 359: 545-550.

Wilson, C.M., C. Kraft, C. Duggan, N. Ismail, S.G. Crawshaw, and S. High. (2005). Ribophorin I associates with a subset of membrane proteins after their integration at the sec61 translocon. J. Biol. Chem. 280: 4195-4206.

Examples:

TC#NameOrganismal TypeExample
9.B.142.1.1

Putative transport protein of 503aas and 9 TMSs

Archaea

Putative transporter of Pyrococcus abyssi (Q9UZC2)

 
9.B.142.1.2

YYY membrane protein of 616aas and 15 TMSs

Archaea

YYY protein of Ferroglobus placidus (D3S2C5)

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.10.1

Putative ABC transporter (shows no sequence similarity to ABC proteins)

Bacteria

Putative ABC transporter of Corynebacterium efficiens (C8NRH5)

 
9.B.142.10.2

Putative ABC -2 transporter/glyceryl transferase

Bacteria

Putative ABC transporter of Rhodococcus erythropolis (C3JPH6)

 
9.B.142.10.3

Hypothetical membrane protein

Bacteria

Hypothetical protein of Thermomicrobium roseum

 
9.B.142.10.4

Hypothetical protein

Bacteria

HP of Terriglobus saanensis

 
9.B.142.10.5

Putative transporter/glycosyltransferase

Proteobacteria

Putative permease of Stigmatella aurantiaca

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.11.1

LphB (10 putative TMSs)

Bacteria

LphB of Legionella pneumophila (O87771)

 
9.B.142.11.10

Uncharacterized protein of 347 aas and 10 TMSs in an apparent 1 + 2 + 2 + 2 +2 + 1 TMS arrangement.

UP of Candidatus Woesebacteria bacterium

 
9.B.142.11.11

Uncharacterized protein of 536 aas and 10 - 12 TMSs.

UP of Sorangium cellulosum

 
9.B.142.11.2

Uncharacterized protein of 589 aas

Actinobacteria

UP of Amycolatopsis mediterranei

 
9.B.142.11.3

Uncharacterized protein of 524 aas and 11 TMSs

Archaea

UP of Methanobacterium formicicum

 
9.B.142.11.4

Uncharacterized protein of 549 aas

Acidobacteria

UP of Choracidobacterium thermophilum

 
9.B.142.11.5

Arabinofuranosyl transferase, AftB, of 575 aas and 13 TMSs

Actinobacteria

AftB of Amycolatopsis orientalis

 
9.B.142.11.6

Arabinofuranosyltransferase, AftB of 533 aas and 9 TMSs

Actinobacteria

AftB of Corynebacterium diphtheriae

 
9.B.142.11.7

Uncharacterized protein of 386 aas and 11 TMSs

UP of Streptomyces niveus

 
9.B.142.11.8

Uncharacterized protein of 370 aas and 10 TMSs.

UP of Pelotomaculum thermopropionicum

 
9.B.142.11.9

Uncharacterized protein of 328 aas and 10 TMSs.

UP of Candidatus Beckwithbacteria bacteriu

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.12.1

PMT_2 superfamily glycosyltransferase, family 39, ArnT, archaeo_STT3, of 604 aas and 12 TMSs.

GT family 39 member of Bdellovibrio bacteriovorus

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.13.1

Glycosyl transferase I, GtrI of 506 aas and 13 TMSs in a 1 + 12 TMS arrangment.

GtrI of Shigella flexneri

 
9.B.142.13.2

Putative glycosyl transferase, GtrI

GtrI of Salmonella enterica

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.14.1

Putative glycosyl transferase of the ArnT and PMT2 families

ArnT homologue of Candidatus Saccharibacteria bacterium

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.15.1

Uncharaterized protein of 579 aas and 10 TMSs.

UP of Lactobacillus casei

 
9.B.142.15.2

Uncharacterized protein of 593 aas and 14 TMSs

UP of Ornalilinea apprima

 
9.B.142.15.3

Uncharacterized protein of 543 aas and 11 TMSs in a 6 + 4 + 1 TMS arrangement

UP of Enterococcus silesiacus

 
9.B.142.15.4

Uncharacterized protein of 569 aas and 10 TMSs

UP of Terriglobus saanensis

 
9.B.142.15.5

Uncharacterized protein of 530 aas

UP of Escherichia fergusonii

 
9.B.142.15.6

Uncharacterized protein of 562 aas and 12 TMSs.

UP of Aeromonas caviae

 
9.B.142.15.7

Uncharacteerized protein of 863 aas and 14 TMSs

UP of Lachnospira pectinoschiza

 
9.B.142.15.8

Dolichyl-phosphate-mannose-protein mannosyltransferase of 749 aas and 14 TMSs

UP of Thermococcus peptonophilus

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.16.1

Glycosyl transferase of 503 aas and 11 TMSs. 

GT of Candidatus Beckwithbacteria bacterium

 
9.B.142.16.2

Glycosyltransferase of 484 aas and 7 - 10 TMSs.

GT of Streptomyces corchorusii

 
9.B.142.16.3

Damage-inducible protein CinA of 512 aas and 9 TMSs.

CinA of Streptococcus pneumoniae

 
9.B.142.16.4

Uncharacterized protein of 455 aas and 9 - 10 TMSs.

UP of Candidatus Daviesbacteria bacterium

 
9.B.142.16.5

Uncharacterized protein of 465 aas and 9 - 11 TMSs.

UP of Flectobacillus major

 
9.B.142.16.6

Uncharacterized protein of 508 aas and 10 TMSs.

UP of Rubrobacter radiotolerans

 
9.B.142.16.7

Glycosyl transferase, family 39 of 535 aas and 12 TMSs.

GT of

Pedosphaera parvula
 
9.B.142.16.8

Uncharacterized protein of 341 aas and 7 - 10 TMSs.

UP of Methanocella conradii

 
9.B.142.16.9

Uncharacterized protein of 523 aas and 10 TMSs.

UP of Runella zeae

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.17.1

Uncharacterized protein of 400 aas and 9 TMSs.

UP of Candidatus Beckwithbacteria bacterium

 
9.B.142.17.2

DUF2029 domain-containing proteinof 504 aas.

DUF2029 protein of Actinoplanes atraurantiacus

 
9.B.142.17.3

Uncharacterized protein of 409 aas and 12 TMSs.

UP of Sphingomonas phyllosphaerae

 
9.B.142.17.4

Uncharacterized protein of 298 aas and 9 TMSs in a 1 + 4 + 4 TMS arrangement.

UP of Candidatus Peribacter riflensis

 
9.B.142.17.5

DUF2029 domain-containing protein of 398 aas and 12 TMSs in a 5 + 2 + 5 arrangement

DUF2029 protein of Agrococcus casei

 
9.B.142.17.6

Uncharacterized protein of 502 aas and 12 TMSs.

UP of Thermogemmatispora onikobensis

 
9.B.142.17.7

Polyprenol-phosphate-mannose-dependent alpha-(1-2)-phosphatidylinositol pentamannoside mannosyltransferase, PimE of 410 aas and 10 TMSs. It is a polyprenol-phosphate-mannose α-mannosyltransferase in the Glycosyltransferase Family 87 (Morita et al. 2006; Belardinelli and Jackson 2017).

PimE of Mycobacterium smegmatis

 
9.B.142.17.8

DUF2339 domain-containing proteinof 637 aas and 19 TMSs.

DUF2339 protein of Rhodococcus fascians

 
9.B.142.17.9

DUF2029 domain-containing protein of 412 aas and 8 - 10 TM

DUF2029 protein of Caballeronia hypogeia

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.18.1

PigM of 825 aas and ~17 TMSs

PigM of Schizosaccharomyces cryophilus

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.19.1

Uncharacterized protein of 463 aas and 12 TMSs in a 9 + 3 TMS arrangement.

UP of Carnobacterium maltaromaticum

 
9.B.142.19.2

Uncharacterized protein of 472 aas and 12 TMSs in a 9 + 3 arrangement.

UP of Planococcaceae bacterium Storch

 
9.B.142.19.3

Uncharacterized protein of 430 aas and 12 TMSs in a 9 + 3 arrangement.

UP of Enterococcus mundtii

 
9.B.142.19.4

Uncharacterized protein of 472 aas and 12 TMSs in a 9 + 3 arrangement.

UP of Blautia sp. AF19-34

 
9.B.142.19.5

Uncharacterized protein of 537 aas and 12 TMSs in a 9 + 3 arrangement

UP of Acutalibacter muris

 
9.B.142.19.6

Uncharacterized protein of 463 aas and 12 TMSs in a 9 + 3 arrangement.

UP of Salilacibacter sp. NKC3-5

 
9.B.142.19.7

O-antigen ligase family protein of 520 aas and 12 TMSs in a 9 + 3 arrangement.

Ligase of Lactobacillus delbrueckii

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.2.1

Glycosyl transferase family 39 protein of 546aas and 13 TMSs

γ-Proteobacteria

GT39 family member of Acidithiobacillus caldus (C6NTX4)

 
9.B.142.2.10

4-Amino-4-deoxy-L-arabinose transferase, ArnT of the glycosyltransferase PMT family.  The structure has been illucidated and the mechanism proposed (VI Petrou et al., Science, vol 351, pg 608, 2016).

ArnT of Cupriavidus metallidurans (Ralstonia metallidurans)

 
9.B.142.2.11

Uncharacterized protein of 807 aas and 17 TMSs in a 1 + 6 + 6 + 4 arrangement.

UP of Oscillochloris trichoides

 
9.B.142.2.12

Uncharacterized glycosyl transferase family 39 of 581 aas and 11 TMSs.

 

UP of Candidatus Wolfebacteria bacterium

 
9.B.142.2.13

Glycosyl transferase of 537 aas and 13 TMSs in a 1 + 6 + 6 arrangement.

GT of Mastigocladopsis repens

 
9.B.142.2.14

Uncharacterized protein of 565 aas and 13 TMSs

UP of Fibrella aestuarina

 
9.B.142.2.15

Uncharacterized protein of 485 aas

UP of Candidatus Magnetobacterium casensis

 
9.B.142.2.16

Uncharacterized protein of 563 aas and 11 - 12 TMSs

UP of Candidatus Peribacter riflensis

 
9.B.142.2.17

Phospholipid carrier-dependent glycosyltransferase of 608 aas and 12 TM

GT of Halostagnicola kamekurae

 
9.B.142.2.18

Uncharacterized protein of 459 aas and 11 TMSs

UP of Candidatus Amesbacteria bacterium

 
9.B.142.2.19

Uncharacterized protein of 448 aas and 13 TMSs.

UP of Candidatus Saccharibacteria bacterium

 
9.B.142.2.2

Putative undecaprenyl phosphate-alpha-4-amino-4-deoxy-L-arabinose arabinosyl transferase, ArnT

Proteobacteria

ArnT of Enterobacter cloacae

 
9.B.142.2.20

Glycosyltransferase family 39 protein of 517 aas with 9 TMSs in a 1 + 2 + 2 + 4 TMS arrangement with a C-terminal 150 aa hydrophilic domain.

Glycosyl transferase of candidate division KSB1 bacterium (aquatic metagenome)

 
9.B.142.2.3

Glycosyl transferase  family PMT

Bacterioidetes

Glycosyl transferase of Zobellia galactivorans

 
9.B.142.2.4

Putative glycosyltransferase

Bacteria

Putative glycosyltransferase of Hydrogenobacter thermophilus

 
9.B.142.2.5

Putative glycosyltransferase with 13 TMSs in a 1 + 6 + 6 TMS topology

Firmicutes

Putative glycosyltransferase of Gordonia rhizosphera

 
9.B.142.2.6

Glycosyl transferase family 39; 4-amino 4-deoxy L-arabinose transferase; Dolichyl phosphate-mannose:protein mannosyl transferase; PMT family; Pfam13231.  528 aas and 13 TMSs

Bacteroidetes

PMT family protein of Solitalea (Flexibacter) canadensis (UPI0003424A3D or YP_0080090676)

 
9.B.142.2.7

Uncharacterized protein of 446 aas.

Proteobacteria

Wzy of Francisella tularensis

 
9.B.142.2.8

Polymyxin resistance protein of 448 aas and 13 TMSs, ArnT.  ArnT catalyzes incorporation of 4-amino-4-deoxy-l-arabinose (l-Ara4N) into the lipid A moiety of lipopolysaccharide (LPS) and is required for transport of LPS to the outer membrane (Tavares-Carreón et al. 2015). ArnT has a 13 TMS topology of key amino acids that contribute to its enzymatic function have been identified (Tavares-Carreón et al. 2015). In response to polymyxin exposure, differentially expressed genes in Acinetobacter baumannii have been identified (Li et al. 2020).

 

Proteobacteria

ArnT of Burkholderia cenocepacia

 
9.B.142.2.9

Undecaprenyl phosphate-alpha-4-amino-4-deoxy-L-arabinose arabinosyl transferase, ArnT, of 550 aas and 13 TMSs.  This modification of LPS is critical for enabling bacteria to resist killing by antimicrobial peptides (Tavares-Carreón et al. 2015).


ArnT of E. coli

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.20.1

Integral membrane serotype-specific glucosyltransferase, GtrV of 417 aas and 9 TMSs (Korres and Verma 2004).

GtrV of Shigella flexneri serotype 5b

 
9.B.142.20.2

Uncharacterized protein of 383 aas and 9 TMSs.

UP of Verrucomicrobia bacterium

 
9.B.142.20.3

Uncharacteerized protein of 432 aas and 10 - 13 TMSs.

UP of Mesorhizobium sp.

 
9.B.142.20.4

Unharacterized protein of 444 aas and 10 - 11 TMSs.

UP of Phormidium sp. GEM2.Bin31 (soda lake metagenome)

 
9.B.142.20.5

Uncharacterized protein of 416 aas and 9 - 11 TMSs.

UP of Lachnospiraceae bacterium (feces metagenome)

 
9.B.142.20.6

Uncharacterized protein of 515 aas and 9 TMSs.

UP of Pseudomonas citronellolis

 
9.B.142.20.7

Uncharacterized protein of 572 aas and 13 TMSs

UP of Thiotrichales bacterium HS_08

 
9.B.142.20.8

Uncharacterized protein of 465 aas and 9 - 11 TMSs

UP of Norcardia sp.

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.3.1

Membrane-bound dolichyl-phosphomannose mannosyltransferase of 814aas and 11-14 TMSs

Archaea

Mannosyltransferase of Thermococcus sibiricus (C6A142)

 
9.B.142.3.10

Uncharacterized protein of 472 aas and 11 TMSs.

Cyanobacteria

UP of Synechocystis sp PCC 6803

 
9.B.142.3.11

Undecaprenyl-diphosphooligosaccharide--protein glycotransferase, PglB.  Oligosaccharyltransferase that catalyzes the transfer of a preassembled heptasaccharide from a lipid donor to an asparagine residue in nascent polypeptide chains, affording a beta-linked glycan to the asparagine side chain of target proteins.  The x-ray structure is known (Lizak et al. 2011).

PglB of Campylobacter lari

 
9.B.142.3.12

Uncharacterized glycosyltransferase of 572 aas and 12 TMSs.

UP of Candidatus Beckwithbacteria bacterium

 
9.B.142.3.13

Mannosyl transferase of 739 aas, PMT_2.

PMT_2 of Methanosaeta harundinacea

 
9.B.142.3.14

The glycosyltransferase complex consisting of 8 subunits, all integral membrane proteins.  The high resolution 3-dimensional structure has been elucidated (Wild et al. 2018). The catalytic subunit is the STT3 protein of 718 aas and 13 TMSs. The other subunits have 1 - 6 TMSs. The function of the complex is glycosylation of newly synthesized proteins on Asn with Glc3Man9 GlcNac2.

Glycosyltransferase complex of Saccharomyces cerevisiae
STT3, P39007, 718 aas amd 13 TMSs - the catalytic subunit
OST1 (Ribophorin I), P41543, 476 aas and 2 TMSs, N- and C-terminal
OST2 (Dad1), P46964, 130 aas and 3 C-terminal TMSs
OST3 (Tusc3), P48439, 350 aas and 6 TMSs in a 2 + 2 +2 arrangement; this protein is a member of the MagT1 family (TC# 1.A.76)
OST4, Q99380, 36 aas and 1 TMS
OST5, (TMEM258), Q92316, 86 aas and 2 TMSs
WBP1 (Ost48), P33767, 430 aas and 2 TMSs, one N-terminal, and one C-terminal
SWP1 (Ribophorin II), Q02795, 286 aas and 4 TMSs, in a 1 (N-terminal) and 3 (C-terminal) arrangement

 
9.B.142.3.15

Dolichyl-phosphooligosaccharide-protein glycotransferase, AglB of 1054 aas and 15 TMSs. This protein is involved in the pathway S-layer biogenesis (Abu-Qarn et al. 2007). AglB exhibits substrate promiscuity, being capable of processing a variety of lipid-linked glycans (Cohen-Rosenzweig et al. 2014).

AglB of Haloferax volcanii (Halobacterium volcanii)

 
9.B.142.3.16

Putative glycosyl transferase of 604 aas and 13 TMSs.

GT of Chloroflexi bacterium

 
9.B.142.3.17

OSTA/B (OST-A/OST-B) complex of 11 subunits.  Most subunits are shared by both complexes except that OSTA has STT3A while OSTB has STT3B, and OSTA has DC2 while OSTB has two parologous Mg2+ porter proteins, MAGT1 (TC# 1.A.76.1) and TUSC3 (TC# 1.A.76.2). The oligosaccharyl transferase (OST) complex catalyzes the initial transfer of a defined glycan (Glc3Man9GlcNAc2 in eukaryotes) from the lipid carrier dolichol-pyrophosphate to an asparagine residue within an Asn-X-Ser/Thr consensus motif in nascent polypeptide chains, the first step in protein N-glycosylation. N-Glycosylation occurs cotranslationally, and the complex associates with the Sec61 complex at the channel-forming translocon complex that mediates protein translocation across the endoplasmic reticulum (ER) membrane. Ribophorin I associates with a subset of membrane proteins after their integration at the Sec61 translocon (Wilson et al. 2005). All subunits are required for maximal enzyme activity. The SST3 subunit contains the active site and the acceptor peptide and donor lipid-linked oligosaccharide (LLO) binding pockets. STT3A is present in the majority of OST complexes and mediates cotranslational N-glycosylation of most sites on target proteins, while STT3B-containing complexes are required for efficient post-translational glycosylation and mediate glycosylation of sites that have been skipped by STT3A (Ruiz-Canada et al. 2009). High-resolution cryo-EM structures of human OST-A and OST-B have been described (Ramírez et al. 2019). Although the two complexes have similar overall architectures, structural differences in the catalytic subunits, STT3A and STT3B, facilitate contacts to distinct OST subunits, DC2 in OST-A and MAGT1 in OST-B. In OST-A, interactions with TMEM258 and STT3A allow ribophorin-I to form a four-helix bundle that can bind to a translating ribosome, whereas the equivalent region is disordered in OST-B. An acceptor peptide and dolichylphosphate are bound to STT3B, but only dolichylphosphate is bound in STT3A, suggesting distinct affinities of the two OST complexes for protein substrates (Ramírez et al. 2019).

The oligosaccharyl transferase (OST) complex of Homo sapiens
STT3A, 705 aas and 13 TMSs; P46977
STT3B (SIMP)13 TMSs in a 1 + 8 +3 + 1 TMS arrangement; Q8TCJ2
Ribophorin-I, RPN1, 607 aas and 4 TMSs in a 1 (N-terminus) + 3 TMS (C-terminus) arrangement; P04843
Ribophorin-2, RPN2, 631 aas and 2 or 3 TMSs; P04844
OST48 (DDOST), 456 aas and 2 TMSs, one N-terminal and one C-terminal, P39656
TMEM258, 79 aas and 2 TMSs; P61165
DAD1, 113 aas and 3 TMSs; P61803
OST4, 37 aas and 1 TMS; P0C6T2
DC2 or OSTC, an adaptor that mediates association with Sec61 for Ost-A
MAGT1, 335 aas and 5 TMSs in a 1 + 2 + 2 TMS arrangement; Q9H0U3
TUSC3, 348 AAS and 5 TMSs
in a 1 + 2 + 2 TMS arrangement; Q13454

 
9.B.142.3.18

Uncharacterized proteini of 747 aas and 19 TMSs. It is possibly related to 9.B.14.

UP of Lokiarchaeum sp GC14-75

 
9.B.142.3.2

Putative glycosyltransferase

Archaea

Putative glycosyltransferase of Pyrococcus horikoshii

 
9.B.142.3.3

Putative glycosyltransferase with a topology of 13 TMSs

Animals

Putative glycosyltransferase of Trichoplax adhaerens (reptans)

 
9.B.142.3.4

Glycosyltransferase

Animals

Glycosyltransferase of Homo sapiens

 
9.B.142.3.5

Glycosyltransferase family 66

Fungi

Glycosyltransferase of Hypocrea atroviridis

 
9.B.142.3.6

Putative glycosyltransferase

Archaea

Putative glycosyltransferase of Methanococcus marpaludis

 
9.B.142.3.7

Putative glycosyltransferase

Firmicutes

Putative glycosyltransferase of Clostridium botulinum

 
9.B.142.3.8

Uncharacterized protein of 522 aas

Firmicutes

UP of Gemella haemolysans

 
9.B.142.3.9

The WlaF protein of 713 aas

Proteobacteria

WlaF of Campylobacter jejuni

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.4.1

Putative glycosyltransferase

Cyanobacteria

Putative glycosyltransferase of Nostoc azollae

 
9.B.142.4.10

Uncharacterized glycosyl transferase family 39 of 640 aas and 11 or 12 putative TMSs.

UP of Candidatus Wolfebacteria bacterium

 
9.B.142.4.11

Uncharacterized protein of 478 aas and 11 TMSs.

UP of Candidatus Woesebacteria bacterium

 
9.B.142.4.12

Uncharaterized glycosyltransferase of 470 aas and 11 TMSs

UP of Candidatus Beckwithbacteria bacterium

 
9.B.142.4.13

Uncharacterized glycosyltransferase of 471 aas and 11 TMSs

UP of Candidatus Beckwithbacteria bacterium

 
9.B.142.4.14

Uncharacterized protein of 514 aas and 11 TMSs

UP of Candidatus Roizmanbacteria bacterium (groundwater metagenome)

 
9.B.142.4.15

Uncharacterized glycosyltransferase of 536 aas and 15 TMSs.

Glycosyltransferase of Candidatus Heimdallarchaeota archaeon LC_3 (marine sediment metagenome)

 
9.B.142.4.16

Putative glycosyltransferase of 603 aas and 11 TMSs. In the PMF2 (Alg9-like) superfamily and the glycosyltransferase-22 superfamily.

Glycosyltransferase of Candidatus Heimdallarchaeota archaeon LC_3

 
9.B.142.4.2

Putative glycosyltransferase

Cyanobacteria

Putative glycosyltransferase of Arthrospira maxima (platensis)

 
9.B.142.4.3

Uncharacterized protein of 493 aas and 11 TMSs

Spirochaetes

UP of Leptospira interrogans

 
9.B.142.4.4

Uncharacterized protein of 825 aas and 11 TMSs

Cyanobacteria

UP of Lyngbya aestuarii

 
9.B.142.4.5

Glycosyl tranferase family 39 protein of 510 aas and 11 TMSs in a 1 + 6 + 4 TMS arrangement.

Euryarchaea

Glycosyl transferase of Methanoregula boonei

 
9.B.142.4.6

Uncharacterized protein of 614 aas and 13 TMSs in a 1 + 6 + 6 TMS arrangement.

Proteobacteria

UP of Desulfatibacillus alkenivorans

 
9.B.142.4.7

UP of 579 aas and 9 TMSs

Cyanobacteria

UP of Oscillatoria nigro-viridis

 
9.B.142.4.8

Uncharacterized protein of 566 aas and 9 TMSs in a 1 + 4 + 4 arrangement

Proteobacteria

UP of Syntrophobacter fumaroxidans

 
9.B.142.4.9

Glycosyl transferase famiy 39; 4-amino 4-deoxy L-arabinose transferase; Pfam13231.  566 aas and 11 TMSs.

Armatimonadetes (Bacteria)

Glycosyltransferase family 39 of Chthonomonas calidirosea

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.5.1

Putative glycosyltransferase of the PMT_2 family

Actinobacteria

Putative glycosyltransferase of Bifidobacterium animalis

 
9.B.142.5.2

Uncharacterized protein of 796 aas and 22 TMSs in a 6 + 6 + 6 + 4 arrangement.

UP of Candidatus Woesebacteria bacterium

 
9.B.142.5.3

Uncharacterized protein of 537 aas and 11 TMSs

UP of Candidatus Amesbacteria bacterium

 
9.B.142.5.4

Phospholipid carrier-dependent glycosyltransferase of 1090 aas and ~24 TMSs.  Repeat sequences have been detected.  

GT of Paenibacillus chitinolyticus

 
9.B.142.5.5

Putative dolichyl-phosphate-mannose--protein mannosyltransferase of 603 aas and 12 TMSs in a 1 + 6 + 5 arrangement.

GT of Butyribacterium methylotrophicum

 
9.B.142.5.6

The structure of the yeast O-mannosyltransferase Pmt1-Pmt2 complex has been determined at 3.2 Å resolution (Bai et al. 2019). In eukaryotes, a nascent peptide entering the endoplasmic reticulum (ER) is scanned by two Sec61 translocon-associated large membrane machines for protein N-glycosylation and protein O-mannosylation, respectively. The structures of both the eight-protein oligosaccharyltransferase complex and the mannosyltransferases of the PMT family have been determined.  They function in ER protein homeostasis. Cryo-EM structures of the Saccharomyces cerevisiae Pmt1-Pmt2 complex bound to a donor and an acceptor peptide shows that each subunit contains 11 TMSs and a lumenal beta-trefoil fold termed the MIR domain. The structures reveal the substrate recognition site and confirms an inverting mannosyl-transferring reaction mechanism. The transmembrane domains of Pmt1 and Pmt2 share a structural fold with the catalytic subunits of oligosaccharyltransferases, confirming an evolutionary relationship between protein O-mannosylation and protein N-glycosylation (Bai et al. 2019).

Pmt1-Pmt2 complex of Saccharomyces cerevisiae

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.6.1

Glycosyltransferase family 39 with a probable 13 TMSs in a 1 + 6 + 6 TMS arrangement.

Acidobacteria

Glycosyltransferase of Terriglobus spanensis

 
9.B.142.6.2

3-amino 4-deoxy L-arabinose transferase-like protein of 524 aas

Firmicutes

Transferase of Thermincola potens

 
9.B.142.6.3

Putative glycosyl transferase of 443 aas and 11 TMSs (Hug et al. 2016).

Glycosyl transferase of Candidatus Peribacter riflensis

 
9.B.142.6.4

Uncharacterized protein of 477 aas and 11 TMSs

UP of Candidatus Desantisbacteria bacterium

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.7.1

Putative glycosyltransferase

Proteobacteria

Putative glycosyltransferase of Rhodopseudomonas palustris

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.8.1

Glycosyltransferase family 39 of 554 aas and 13 putative TMSs

Spirochaetes

Glycosyltransferase of Leptonema illini

 
Examples:

TC#NameOrganismal TypeExample
9.B.142.9.1

Glycosyltransferase of 463 aas and 7 TMSs (family 39; the PMT_2 superfamily).

Planctomycetes

Glycosyltransferase of Rhodopirellula baltica

 
9.B.142.9.10

Uncharacterized protein with no conserved domain recognized by CDD.  527 aas and 9 - 10 TMSs in a 1 + 4 + 4 arrangement.

UP of Candidatus Beckwithbacteria bacterium

 
9.B.142.9.11

Uncharacterized protein of 565 aas and 9 - 12 TMSs.

UP of Candidatus Roizmanbacteria bacterium

 
9.B.142.9.12

Dolichyl-phosphate-mannose--protein mannosyltransferase of 502 aas and 11 TMSs.

MT of Leptospira vanthielii

 
9.B.142.9.13

Uncharacteerized protein of 511 aas and 11 TMSs.

UP of Clostridium baratii

 
9.B.142.9.14

Uncharacterized protein of 507 aas and 11 TMSs.

UP of Acetobacter tropicalis

 
9.B.142.9.15

Uncharacterized protein of 488 aas and 10 TMSs.

UP of Novosphingobium pentaromativorans

 
9.B.142.9.16

DUF2723 domain-containing protein of 1090 aas and 13 TMSs.

DUF2723 protein of Kordia periserrulae

 
9.B.142.9.17

DUF2029 domain-containing protein of 418 aas and 9 - 11 TMSs.  Possibly a dolichyl-P-mannose mannosyl transferase. It is a member of the PMT_2 superfamily of mannosyltransferases.

DUF2029 protein of Adhaeribacter aquaticus

 
9.B.142.9.18

PMT_2 superfamily membeer of 424 aas and about 12 TMSs.

PMT_2 family member of Lokiarchaeum sp. GC14_75

 
9.B.142.9.2

Uncharacterized protein of 417 aas and 11 TMSs.

Acidobacteria

UP of Chloracidobacterium thermophilum

 
9.B.142.9.3

Glycosyltransferase family protein of 430 aas and 8 TMSs.

Firmicutes

UP of Clostridium thermocellum

 
9.B.142.9.4

Uncharacterized protein of 409 aas and 10 TMSs

Firmicutes

UP of Kyrpidia (Bacillus) tusciae

 
9.B.142.9.5

Uncharacterized protein of 542 aas and 10 TMSs

Acidobacteria

UP of Granulicella tundricola

 
9.B.142.9.6

Uncharacterized protein of 669 aas and 15 TMSs

Archaea

UP of Pyrococcus horikoshii

 
9.B.142.9.7

Uncharacterized DUF2070 domain protein of 688 aas and 15 TMSs.

UP of Anaerolinea thermolimosa

 
9.B.142.9.8

Uncharacterized protein of 523 aas and 9 TMSs with a 1 + 4 + 4 TMS pattern.

UP of Microgenomates bacterium

 
9.B.142.9.9

DUF2723 domain-containing protein of 455 aas and 9 TMSs in a 1 + 4 + 4 arrangement.

UP of Herpetosiphon geysericola