EC 2.4.99

Contents

Entries

[EC 2.4.99.2 Transferred entry: β-D-galactosyl-(1→3)-N-acetyl-β-D-galactosaminide α-2,3-sialyltransferase. Now EC 2.4.3.2, β-D-galactosyl-(1→3)-N-acetyl-β-D-galactosaminide α-2,3-sialyltransferase (EC 2.4.99.2 created 1976, modified 1986, deleted 2022)]

[EC 2.4.99.3 Transferred entry: α-N-acetylgalactosaminide α-2,6-sialyltransferase. Now EC 2.4.3.3, α-N-acetylgalactosaminide α-2,6-sialyltransferase (EC 2.4.99.3 created 1984, modified 1986, deleted 2022)]

[EC 2.4.99.4 Transferred entry: β-galactoside α-2,3-sialyltransferase. Now EC 2.4.3.4, β-galactoside α-2,3-sialyltransferase (EC 2.4.99.4 created 1984, modified 1986, deleted 2022)]

[EC 2.4.99.5 Transferred entry: galactosyldiacylglycerol α-2,3-sialyltransferase. Now EC 2.4.3.5, galactosyldiacylglycerol α-2,3-sialyltransferase (EC 2.4.99.5 created 1984, modified 1986, deleted 2022)]

[EC 2.4.99.6 Transferred entry: N-acetyllactosaminide α-2,3-sialyltransferase. Now EC 2.4.3.6, N-acetyllactosaminide α-2,3-sialyltransferase (EC 2.4.99.6 created 1984, modified 1986 (EC 2.4.99.10 created 1986, incorporated 2017), deleted 2022)]

[EC 2.4.99.7 Transferred entry: α-N-acetylneuraminyl-2,3-β-galactosyl-1,3-N-acetylgalactosaminide 6-α-sialyltransferase. Now EC 2.4.3.7, α-N-acetylneuraminyl-2,3-β-galactosyl-1,3-N-acetylgalactosaminide 6-α-sialyltransferase (EC 2.4.99.7 created 1984, modified 1986, modified 2004, deleted 2022)]

[EC 2.4.99.8 Transferred entry: α-N-acetylneuraminate α-2,8-sialyltransferase. Now EC 2.4.3.8, α-N-acetylneuraminate α-2,8-sialyltransferase (EC 2.4.99.8 created 1984, modified 1986, deleted 2022)]

[EC 2.4.99.9 Transferred entry: lactosylceramide α-2,3-sialyltransferase. Now EC 2.4.3.9, lactosylceramide α-2,3-sialyltransferase (EC 2.4.99.9 created 1984, modified 1986, deleted 2022)]

[EC 2.4.99.10 Transferred entry: neolactotetraosylceramide α-2,3-sialyltransferase. Now included in EC 2.4.3.6, N-acetyllactosaminide α-2,3-sialyltransferase (EC 2.4.99.10 created 1986, deleted 2017)]

[EC 2.4.99.11 Deleted entry: lactosylceramide α-2,6-N-sialyltransferase, now included with EC 2.4.3.1, β-galactoside α-2,6-sialyltransferase (EC 2.4.99.11 created 1992, deleted 2016)]

EC 2.4.99.12

Accepted name: lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase

Reaction: CMP-β-Kdo + a lipid IV_A + CMP-β-Kdo = CMP + an α-Kdo-(2→6)-[lipid IV_A]

For diagram of reaction click here.

Glossary: lipid IV_A = 2-deoxy-2-{[(3R)-3-hydroxyacyl]amino}-3-O-[(3R)-3-hydroxyacyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxyacyl]-2-{[(3R)-3-hydroxyacyl]amino}-1-O-phosphono-α-D-glucopyranose
CMP-β-Kdo = CMP-3-deoxy-&bet;-D-manno-oct-2-ulopyranosylonate

Other name(s): KDO transferase; waaA (gene name); kdtA (gene name); 3-deoxy-D-manno-oct-2-ulosonic acid transferase; 3-deoxy-manno-octulosonic acid transferase; lipid IV_A KDO transferase

Systematic name: CMP-3-deoxy-D-manno-oct-2-ulosonate:lipid IV_A 3-deoxy-D-manno-oct-2-ulosonate transferase

Comments: The bifunctional enzyme from Escherichia coli transfers two 3-deoxy-D-manno-oct-2-ulosonate residues to lipid IV_A (cf. EC 2.4.99.13 [(KDO)-lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase]) [1]. The monofunctional enzymes from Aquifex aeolicus and Haemophilus influenzae catalyse the transfer of a single 3-deoxy-D-manno-oct-2-ulosonate residue from CMP-3-deoxy-D-manno-oct-2-ulosonate to lipid IV_A [2,3]. The enzymes from Chlamydia transfer three or more 3-deoxy-D-manno-oct-2-ulosonate residues and generate genus-specific epitopes [4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Belunis, C.J. and Raetz, C.R. Biosynthesis of endotoxins. Purification and catalytic properties of 3-deoxy-D-manno-octulosonic acid transferase from Escherichia coli. J. Biol. Chem. 267 (1992) 9988-9997. [PMID: 1577828]

2. Mamat, U., Schmidt, H., Munoz, E., Lindner, B., Fukase, K., Hanuszkiewicz, A., Wu, J., Meredith, T.C., Woodard, R.W., Hilgenfeld, R., Mesters, J.R. and Holst, O. WaaA of the hyperthermophilic bacterium Aquifex aeolicus is a monofunctional 3-deoxy-D-manno-oct-2-ulosonic acid transferase involved in lipopolysaccharide biosynthesis. J. Biol. Chem. 284 (2009) 22248-22262. [PMID: 19546212]

3. White, K.A., Kaltashov, I.A., Cotter, R.J. and Raetz, C.R. A mono-functional 3-deoxy-D-manno-octulosonic acid (Kdo) transferase and a Kdo kinase in extracts of Haemophilus influenzae. J. Biol. Chem. 272 (1997) 16555-16563. [PMID: 9195966]

4. Lobau, S., Mamat, U., Brabetz, W. and Brade, H. Molecular cloning, sequence analysis, and functional characterization of the lipopolysaccharide biosynthetic gene kdtA encoding 3-deoxy-α-D-manno-octulosonic acid transferase of Chlamydia pneumoniae strain TW-183. Mol. Microbiol. 18 (1995) 391-399. [PMID: 8748024]

EC 2.4.99.13

Accepted name: (Kdo)-lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase

Reaction: CMP-β-Kdo + an α-Kdo-(2→6)-[lipid IV_A] = CMP + an α-Kdo-(2→4)-α-Kdo-(2→6)-[lipid IV_A]

For diagram of reaction click here

Glossary: CMP-β-Kdo = CMP-3-deoxy-β-D-manno-oct-2-ulopyranosylonate
a lipid IV_A = 2-deoxy-2-{[(3R)-3-hydroxyacyl]amino}-3-O-[(3R)-3-hydroxyacyl]-4-O-phospho-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxyacyl]-2-{[(3R)-3-hydroxyacyl]amino}-1-O-phospho-α-D-glucopyranose

Other name(s): waaA (gene name); kdtA (gene name); 3-deoxy-D-manno-oct-2-ulosonic acid transferase; 3-deoxy-manno-octulosonic acid transferase; (KDO)-lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase; CMP-3-deoxy-D-manno-oct-2-ulosonate:(Kdo)-lipid IV_A 3-deoxy-D-manno-oct-2-ulosonate transferase; Kdo transferase (ambiguous)

Systematic name: CMP-3-deoxy-β-D-manno-oct-2-ulosonate:α-Kdo-(2→6)-[lipid IV_A] 3-deoxy-D-manno-oct-2-ulosonate transferase (configuration-inverting)

Comments: The enzyme from Escherichia coli is bifunctional and transfers two 3-deoxy-D-manno-oct-2-ulosonate residues to lipid IV_A (cf. EC 2.4.99.12 [lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase]) [1]. The enzymes from Chlamydia transfer three or more 3-deoxy-D-manno-oct-2-ulosonate residues and generate genus-specific epitopes [2].

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Belunis, C.J. and Raetz, C.R. Biosynthesis of endotoxins. Purification and catalytic properties of 3-deoxy-D-manno-octulosonic acid transferase from Escherichia coli, J. Biol. Chem. 267 (1992) 9988-9997. [PMID: 1577828]

2. Lobau, S., Mamat, U., Brabetz, W. and Brade, H. Molecular cloning, sequence analysis, and functional characterization of the lipopolysaccharide biosynthetic gene kdtA encoding 3-deoxy-α-D-manno-octulosonic acid transferase of Chlamydia pneumoniae strain TW-183. Mol. Microbiol. 18 (1995) 391-399. [PMID: 8748024]

3. Schmidt, H., Hansen, G., Singh, S., Hanuszkiewicz, A., Lindner, B., Fukase, K., Woodard, R.W., Holst, O., Hilgenfeld, R., Mamat, U. and Mesters, J.R. Structural and mechanistic analysis of the membrane-embedded glycosyltransferase WaaA required for lipopolysaccharide synthesis. Proc. Natl. Acad. Sci. USA 109 (2012) 6253-6258. [PMID: 22474366]

EC 2.4.99.14

Accepted name: (KDO)₂-lipid IV_A (2-8) 3-deoxy-D-manno-octulosonic acid transferase

Reaction: α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A + CMP-β-Kdo = α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A + CMP

For diagram of reaction click here.

Glossary: (KDO)₂-lipid IV_A = α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
(KDO)₃-lipid IV_A = α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→8)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
CMP-β-Kdo = CMP-3-deoxy-β-D-manno-oct-2-ulopyranosylonate

Other name(s): KDO transferase; waaA (gene name); kdtA (gene name); 3-deoxy-D-manno-oct-2-ulosonic acid transferase; 3-deoxy-manno-octulosonic acid transferase

Systematic name: CMP-3-deoxy-D-manno-oct-2-ulosonate:(KDO)₂-lipid IV_A 3-deoxy-D-manno-oct-2-ulosonate transferase [(2→8) glycosidic bond-forming]

Comments: The enzymes from Chlamydia transfer three or more 3-deoxy-D-manno-oct-2-ulosonate residues and generate genus-specific epitopes.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Lobau, S., Mamat, U., Brabetz, W. and Brade, H. Molecular cloning, sequence analysis, and functional characterization of the lipopolysaccharide biosynthetic gene kdtA encoding 3-deoxy-α-D-manno-octulosonic acid transferase of Chlamydia pneumoniae strain TW-183. Mol. Microbiol. 18 (1995) 391-399. [PMID: 8748024]

2. Mamat, U., Baumann, M., Schmidt, G. and Brade, H. The genus-specific lipopolysaccharide epitope of Chlamydia is assembled in C. psittaci and C. trachomatis by glycosyltransferases of low homology. Mol. Microbiol. 10 (1993) 935-941. [PMID: 7523826]

3. Belunis, C.J., Mdluli, K.E., Raetz, C.R. and Nano, F.E. A novel 3-deoxy-D-manno-octulosonic acid transferase from Chlamydia trachomatis required for expression of the genus-specific epitope. J. Biol. Chem. 267 (1992) 18702-18707. [PMID: 1382060]

EC 2.4.99.15

Accepted name: (KDO)₃-lipid IV_A (2-4) 3-deoxy-D-manno-octulosonic acid transferase

Reaction: α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A + CMP-β-Kdo = α-Kdo-(2→8)-[α-Kdo-(2→4)]-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A + CMP

For diagram of reaction click here.

Glossary: (KDO)₃-lipid IV_A = α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→8)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
(KDO)₄-lipid IV_A = α-Kdo-(2→8)-[α-Kdo-(2→4)]-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IV_A = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→8)-[(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
CMP-β-Kdo = CMP-3-deoxy-β-D-manno-oct-2-ulopyranosylonate

Other name(s): KDO transferase; waaA (gene name); kdtA (gene name); 3-deoxy-D-manno-oct-2-ulosonic acid transferase; 3-deoxy-manno-octulosonic acid transferase

Systematic name: CMP-3-deoxy-D-manno-oct-2-ulosonate:(KDO)₃-lipid IV_A 3-deoxy-D-manno-oct-2-ulosonate transferase [(2→4) glycosidic bond-forming]

Comments: The enzyme from Chlamydia psittaci transfers four KDO residues to lipid A, forming a branched tetrasaccharide with the structure α-KDO-(2,8)-[α-KDO-(2,4)]-α-KDO-(2,4)-α-KDO (cf. EC 2.4.99.12 [lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase], EC 2.4.99.13 [(KDO)-lipid IV_A 3-deoxy-D-manno-octulosonic acid transferase], and EC 2.4.99.14 [(KDO)₂-lipid IV_A (2-8) 3-deoxy-D-manno-octulosonic acid transferase]).

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:

References:

1. Brabetz, W., Lindner, B. and Brade, H. Comparative analyses of secondary gene products of 3-deoxy-D-manno-oct-2-ulosonic acid transferases from Chlamydiaceae in Escherichia coli K-12. Eur. J. Biochem. 267 (2000) 5458-5465. [PMID: 10951204]

2. Holst, O., Bock, K., Brade, L. and Brade, H. The structures of oligosaccharide bisphosphates isolated from the lipopolysaccharide of a recombinant Escherichia coli strain expressing the gene gseA [3-deoxy-D-manno-octulopyranosonic acid (Kdo) transferase] of Chlamydia psittaci 6BC. Eur. J. Biochem. 229 (1995) 194-200. [PMID: 7744029]

EC 2.4.99.16

Accepted name: starch synthase (maltosyl-transferring)

Reaction: α-maltose 1-phosphate + [(1→4)-α-D-glucosyl]_n = phosphate + [(1→4)-α-D-glucosyl]_n+2

Other name(s): α1,4-glucan:maltose-1-P maltosyltransferase; GMPMT

Glossary: 7-aminomethyl-7-carbaguanine = preQ₁ = 7-aminomethyl-7-deazaguanine
epoxyqueosine = oQ

Systematic name: α-maltose 1-phosphate:(1→4)-α-D-glucan 4-α-D-maltosyltransferase

Comments: The enzyme from from the bacterium Mycobacterium smegmatis is specific for maltose. It has no activity with α-D-glucose.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Elbein, A.D., Pastuszak, I., Tackett, A.J., Wilson, T. and Pan, Y.T. Last step in the conversion of trehalose to glycogen: a mycobacterial enzyme that transfers maltose from maltose 1-phosphate to glycogen. J. Biol. Chem. 285 (2010) 9803-9812. [PMID: 20118231]

2. Syson, K., Stevenson, C.E., Rejzek, M., Fairhurst, S.A., Nair, A., Bruton, C.J., Field, R.A., Chater, K.F., Lawson, D.M. and Bornemann, S. Structure of Streptomyces maltosyltransferase GlgE, a homologue of a genetically validated anti-tuberculosis target. J. Biol. Chem. 286 (2011) 38298-38310. [PMID: 21914799]

EC 2.4.99.17

Accepted name: S-adenosylmethionine:tRNA ribosyltransferase-isomerase

Reaction: S-adenosyl-L-methionine + 7-aminomethyl-7-carbaguanosine³⁴ in tRNA = L-methionine + adenine + epoxyqueuosine³⁴ in tRNA

For diagram of reaction click here and mechanism click here.

Glossary: 7-aminomethyl-7-carbaguanine = 7-aminomethyl-7-deazaguanine = preQ₁
epoxyqueosine = oQ

Other name(s): QueA enzyme; queuosine biosynthesis protein QueA

Systematic name: S-adenosyl-L-methionine:7-aminomethyl-7-deazaguanosine ribosyltransferase (ribosyl isomerizing; L-methionine, adenine releasing)

Comments: The reaction is a combined transfer and isomerization of the ribose moiety of S-adenosyl-L-methionine to the modified guanosine base in the wobble position in tRNAs specific for Tyr, His, Asp or Asn. It is part of the queuosine biosynthesis pathway.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Slany, R.K., Bosl, M., Crain, P.F. and Kersten, H. A new function of S-adenosylmethionine: the ribosyl moiety of AdoMet is the precursor of the cyclopentenediol moiety of the tRNA wobble base queuine. Biochemistry 32 (1993) 7811-7817. [PMID: 8347586]

2. Slany, R.K., Bosl, M. and Kersten, H. Transfer and isomerization of the ribose moiety of AdoMet during the biosynthesis of queuosine tRNAs, a new unique reaction catalyzed by the QueA protein from Escherichia coli. Biochimie 76 (1994) 389-393. [PMID: 7849103]

3. Kinzie, S.D., Thern, B. and Iwata-Reuyl, D. Mechanistic studies of the tRNA-modifying enzyme QueA: a chemical imperative for the use of AdoMet as a "ribosyl" donor. Org. Lett. 2 (2000) 1307-1310. [PMID: 10810734]

4. Van Lanen, S.G. and Iwata-Reuyl, D. Kinetic mechanism of the tRNA-modifying enzyme S-adenosylmethionine:tRNA ribosyltransferase-isomerase (QueA). Biochemistry 42 (2003) 5312-5320. [PMID: 12731872]

5. Mathews, I., Schwarzenbacher, R., McMullan, D., Abdubek, P., Ambing, E., Axelrod, H., Biorac, T., Canaves, J.M., Chiu, H.J., Deacon, A.M., DiDonato, M., Elsliger, M.A., Godzik, A., Grittini, C., Grzechnik, S.K., Hale, J., Hampton, E., Han, G.W., Haugen, J., Hornsby, M., Jaroszewski, L., Klock, H.E., Koesema, E., Kreusch, A., Kuhn, P., Lesley, S.A., Levin, I., Miller, M.D., Moy, K., Nigoghossian, E., Ouyang, J., Paulsen, J., Quijano, K., Reyes, R., Spraggon, G., Stevens, R.C., van den Bedem, H., Velasquez, J., Vincent, J., White, A., Wolf, G., Xu, Q., Hodgson, K.O., Wooley, J. and Wilson, I.A. Crystal structure of S-adenosylmethionine:tRNA ribosyltransferase-isomerase (QueA) from Thermotoga maritima at 2.0 Å resolution reveals a new fold. Proteins 59 (2005) 869-874. [PMID: 15822125]

6. Grimm, C., Ficner, R., Sgraja, T., Haebel, P., Klebe, G. and Reuter, K. Crystal structure of Bacillus subtilis S-adenosylmethionine:tRNA ribosyltransferase-isomerase. Biochem. Biophys. Res. Commun. 351 (2006) 695-701. [PMID: 17083917]

EC 2.4.99.18

Accepted name: dolichyl-diphosphooligosaccharide—protein glycotransferase

Reaction: dolichyl diphosphooligosaccharide + [protein]-L-asparagine = dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-β-D-glycosyl linkage to a protein L-asparagine

For diagram of reaction click here.

Other name(s): dolichyldiphosphooligosaccharide-protein glycosyltransferase; asparagine N-glycosyltransferase; dolichyldiphosphooligosaccharide-protein oligosaccharyltransferase; dolichylpyrophosphodiacetylchitobiose-protein glycosyltransferase; oligomannosyltransferase; oligosaccharide transferase; dolichyldiphosphoryloligosaccharide-protein oligosaccharyltransferase; dolichyl-diphosphooligosaccharide:protein-L-asparagine oligopolysaccharidotransferase; STT3

Systematic name: dolichyl-diphosphooligosaccharide:protein-L-asparagine N-β-D-oligopolysaccharidotransferase

Comments: Occurs in eukaryotes that form a glycoprotein by the transfer of a glucosyl-mannosyl-glucosamine polysaccharide to the side-chain of an L-asparagine residue in the sequence -Asn-Xaa-Ser- or -Asn-Xaa-Thr- (Xaa not Pro) in nascent polypeptide chains. The basic oligosaccharide is the tetradecasaccharide Glc₃Man₉GlcNAc₂ (for diagram click here). However, smaller oligosaccharides derived from it and oligosaccharides with additional monosaccharide units attached may be involved. See ref [2] for a review of N-glycoproteins in eukaryotes. Man₃GlcNAc₂ seems to be common for all of the oligosaccharides involved with the terminal N-acetylglucosamine linked to the protein L-asparagine. Occurs on the cytosolic face of the endoplasmic reticulum. The dolichol involved normally has 14-21 isoprenoid units with two trans double-bonds at the ω end, and the rest of the double-bonds in cis form.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 75302-32-8

References:

1. Das, R.C. and Heath, E.C. Dolichyldiphosphoryloligosaccharide-protein oligosaccharyltransferase; solubilization, purification, and properties. Proc. Natl. Acad. Sci. USA 77 (1980) 3811-3815. [PMID: 6933437]

2. Song, W., Henquet, M.G., Mentink, R.A., van Dijk, A.J., Cordewener, J.H., Bosch, D., America, A.H. and van der Krol, A.R. N-glycoproteomics in plants: perspectives and challenges. J Proteomics 74 (2011) 1463-1474. [PMID: 21605711]

EC 2.4.99.19

Accepted name: undecaprenyl-diphosphooligosaccharide—protein glycotransferase

Reaction: tritrans,heptacis-undecaprenyl diphosphooligosaccharide + [protein]-L-asparagine = tritrans,heptacis-undecaprenyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-β-D-glycosyl linkage to protein L-asparagine

For diagram of reaction click here.

Other name(s): PglB

Systematic name: tritrans,heptacis-undecaprenyl-diphosphooligosaccharide:protein-L-asparagine N-β-D-oligosaccharidotransferase

Comments: A bacterial enzyme that has been isolated from Campylobacter jejuni [1] and Campylobacter lari [2]. It forms a glycoprotein by the transfer of a glucosyl-N-acetylgalactosaminyl-N,N'-diacetylbacillosamine (GalNAc₂(Glc)GalNAc₃diNAcBac) polysaccharide and related oligosaccharides to the side-chain of an L-asparagine residue in the sequence -Asp/Glu-Xaa-Asn-Xaa'-Ser/Thr- (Xaa and Xaa' not Pro) in nascent polypeptide chains. Requires Mn²⁺ or Mg²⁺. Occurs on the external face of the plasma membrane. The polyprenol involved is normally tritrans,heptacis-undecaprenol but a decaprenol is used by some species.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:

References:

1. Maita, N., Nyirenda, J., Igura, M., Kamishikiryo, J. and Kohda, D. Comparative structural biology of eubacterial and archaeal oligosaccharyltransferases. J. Biol. Chem. 285 (2010) 4941-4950. [PMID: 20007322]

2. Lizak, C., Gerber, S., Numao, S., Aebi, M. and Locher, K.P. X-ray structure of a bacterial oligosaccharyltransferase. Nature 474 (2011) 350-355. [PMID: 21677752]

EC 2.4.99.20

Accepted name: 2'-phospho-ADP-ribosyl cyclase/2'-phospho-cyclic-ADP-ribose transferase

Reaction: NADP⁺ + nicotinate = nicotinate-adenine dinucleotide phosphate + nicotinamide (overall reaction)
(1a) NADP⁺ = 2'-phospho-cyclic ADP-ribose + nicotinamide
(1b) 2'-phospho-cyclic ADP-ribose + nicotinate = nicotinate-adenine dinucleotide phosphate

For diagram of reaction click here.

Glossary: 2'-phospho-cyclic ADP-ribose = cADPRP
nicotinic acid-adenine dinucleotide phosphate = NAADP⁺

Other name(s): diphosphopyridine nucleosidase (ambiguous); CD38 (gene name); BST1 (gene name)

Systematic name: NADP⁺:nicotinate ADP-ribosyltransferase

Comments: This multiunctional enzyme catalyses both the removal of nicotinamide from NADP⁺, forming 2'-phospho-cyclic ADP-ribose, and the addition of nicotinate to the cyclic product, forming NAADP⁺, a calcium messenger that can mobilize intracellular Ca²⁺ stores and activate Ca²⁺ influx to regulate a wide range of physiological processes. In addition, the enzyme also catalyses EC 3.2.2.6, ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Chini, E.N., Chini, C.C., Kato, I., Takasawa, S. and Okamoto, H. CD38 is the major enzyme responsible for synthesis of nicotinic acid-adenine dinucleotide phosphate in mammalian tissues. Biochem. J. 362 (2002) 125-130. [PMID: 11829748]

2. Moreschi, I., Bruzzone, S., Melone, L., De Flora, A. and Zocchi, E. NAADP⁺ synthesis from cADPRP and nicotinic acid by ADP-ribosyl cyclases. Biochem. Biophys. Res. Commun. 345 (2006) 573-580. [PMID: 16690024]

EC 2.4.99.21

Accepted name: dolichyl-phosphooligosaccharide-protein glycotransferase

Reaction: an archaeal dolichyl phosphooligosaccharide + [protein]-L-asparagine = an archaeal dolichyl phosphate + a glycoprotein with the oligosaccharide chain attached by N-β-D-glycosyl linkage to a protein L-asparagine

Other name(s): AglB; archaeal oligosaccharyl transferase; dolichyl-monophosphooligosaccharide-protein glycotransferase

Systematic name: dolichyl-phosphooligosaccharide:protein-L-asparagine N-β-D-oligosaccharidotransferase

Comments: The enzyme, characterized from the archaea Methanococcus voltae and Haloferax volcanii, transfers a glycan component from dolichyl phosphooligosaccharide to external proteins. It is different from EC 2.4.99.18, dolichyl-diphosphooligosaccharide-protein glycotransferase, which uses dolichyl diphosphate as carrier compound in bacteria and eukaryotes. The enzyme participates in the N-glycosylation of proteins in some archaea. It requires Mn²⁺. Dolichol used by archaea is different from that used by eukaryotes. It is much shorter (C₅₅-C₆₀), it is α,ω-saturated and it may have additional unsaturated positions in the chain.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Chaban, B., Voisin, S., Kelly, J., Logan, S.M. and Jarrell, K.F. Identification of genes involved in the biosynthesis and attachment of Methanococcus voltae N-linked glycans: insight into N-linked glycosylation pathways in Archaea. Mol. Microbiol. 61 (2006) 259-268. [PMID: 16824110]

2. Larkin, A., Chang, M.M., Whitworth, G.E. and Imperiali, B. Biochemical evidence for an alternate pathway in N-linked glycoprotein biosynthesis. Nat. Chem. Biol. 9 (2013) 367-373. [PMID: 23624439]

3. Cohen-Rosenzweig, C., Guan, Z., Shaanan, B. and Eichler, J. Substrate promiscuity: AglB, the archaeal oligosaccharyltransferase, can process a variety of lipid-linked glycans. Appl. Environ. Microbiol. 80 (2014) 486-496. [PMID: 24212570]

[EC 2.4.99.22 Transferred entry: N-acetylglucosaminide α-(2,6)-sialyltransferase. Now EC 2.4.3.10, N-acetylglucosaminide α-(2,6)-sialyltransferase (EC 2.4.99.22 created 2020, deleted 2022)]

EC 2.4.99.23

Accepted name: lipopolysaccharide heptosyltransferase I

Reaction: ADP-L-glycero-β-D-manno-heptose + an α-Kdo-(2→4)-α-Kdo-(2→6)-[lipid A] = ADP + an α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A]

Glossary: Lipid A is a lipid component of the lipopolysaccharides (LPS) of Gram-negative bacteria. It consists of two glucosamine units connected by a β(1→6) bond and decorated with four to seven acyl chains and up to two phosphate groups.
Hep = L-glycero-D-manno-heptose

Other name(s): HepI; rfaC (gene name); WaaC; heptosyltransferase I (ambiguous)

Systematic name: ADP-L-glycero-β-D-manno-heptose:an α-Kdo-(2→4)-α-Kdo-(2→6)-[lipid A] 5-α-heptosyltransferase

Comments: The enzyme catalyses a glycosylation step in the biosynthesis of the inner core oligosaccharide of the lipopolysaccharide (endotoxin) of many Gram-negative bacteria.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:

References:

1. Kadrmas, J.L. and Raetz, C.R. Enzymatic synthesis of lipopolysaccharide in Escherichia coli. Purification and properties of heptosyltransferase i. J. Biol. Chem. 273 (1998) 2799-2807. [PMID: 9446588]

2. de Kievit, T.R. and Lam, J.S. Isolation and characterization of two genes, waaC (rfaC) and waaF (rfaF), involved in Pseudomonas aeruginosa serotype O5 inner-core biosynthesis. J. Bacteriol. 179 (1997) 3451-3457. [PMID: 9171387]

3. Klena, J.D., Gray, S.A. and Konkel, M.E. Cloning, sequencing, and characterization of the lipopolysaccharide biosynthetic enzyme heptosyltransferase I gene (waaC) from Campylobacter jejuni and Campylobacter coli. Gene 222 (1998) 177-185. [PMID: 9831648]

4. Gronow, S., Oertelt, C., Ervela, E., Zamyatina, A., Kosma, P., Skurnik, M. and Holst, O. Characterization of the physiological substrate for lipopolysaccharide heptosyltransferases I and II. J Endotoxin Res 7 (2001) 263-270. [PMID: 11717579]

5. Grizot, S., Salem, M., Vongsouthi, V., Durand, L., Moreau, F., Dohi, H., Vincent, S., Escaich, S. and Ducruix, A. Structure of the Escherichia coli heptosyltransferase WaaC: binary complexes with ADP and ADP-2-deoxy-2-fluoro heptose. J. Mol. Biol. 363 (2006) 383-394. [PMID: 16963083]

EC 2.4.99.24

Accepted name: lipopolysaccharide heptosyltransferase II

Reaction: ADP-L-glycero-β-D-manno-heptose + an α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] = ADP + an α-Hep-(1→3)-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A]

Glossary: Lipid A is a lipid component of the lipopolysaccharides (LPS) of Gram-negative bacteria. It consists of two glucosamine units connected by a β(1→6) bond and decorated with four to seven acyl chains and up to two phosphate groups.
Hep = L-glycero-D-manno-heptose

Other name(s): HepII; rfaF (gene name); WaaF; heptosyltransferase II

Systematic name: ADP-L-glycero-β-D-manno-heptose:an α-L-glycero-D-manno-heptosyl-(1→5)-[α-Kdo-(2→4)]-α -Kdo-(2→6)-[lipid A] 3-α-heptosyltransferase

Comments: The enzyme catalyses a glycosylation step in the biosynthesis of the inner core oligosaccharide of the lipopolysaccharide (endotoxin) of some Gram-negative bacteria.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Allen, A.G., Isobe, T. and Maskell, D.J. Identification and cloning of waaF (rfaF) from Bordetella pertussis and use to generate mutants of Bordetella spp. with deep rough lipopolysaccharide. J. Bacteriol. 180 (1998) 35-40. [PMID: 9422589]

2. Bauer, B.A., Lumbley, S.R. and Hansen, E.J. Characterization of a WaaF (RfaF) homolog expressed by Haemophilus ducreyi. Infect. Immun. 67 (1999) 899-907. [PMID: 9916106]

3. Gronow, S., Brabetz, W. and Brade, H. Comparative functional characterization in vitro of heptosyltransferase I (WaaC) and II (WaaF) from Escherichia coli. Eur. J. Biochem. 267 (2000) 6602-6611. [PMID: 11054112]

4. Gronow, S., Oertelt, C., Ervela, E., Zamyatina, A., Kosma, P., Skurnik, M. and Holst, O. Characterization of the physiological substrate for lipopolysaccharide heptosyltransferases I and II. J Endotoxin Res 7 (2001) 263-270. [PMID: 11717579]

5. Oldfield, N.J., Moran, A.P., Millar, L.A., Prendergast, M.M. and Ketley, J.M. Characterization of the Campylobacter jejuni heptosyltransferase II gene, waaF, provides genetic evidence that extracellular polysaccharide is lipid A core independent. J. Bacteriol. 184 (2002) 2100-2107. [PMID: 11914340]

EC 2.4.99.25

Accepted name: lipopolysaccharide heptosyltransferase III

Reaction: ADP-L-glycero-β-D-manno-heptose + an α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] = ADP + an α-Hep-(1→7)-α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A]

Glossary: Lipid A is a lipid component of the lipopolysaccharides (LPS) of Gram-negative bacteria. It consists of two glucosamine units connected by a β(1→6) bond and decorated with four to seven acyl chains and up to two phosphate groups.
Hep = L-glycero-D-manno-heptose

Other name(s): waaQ (gene name); rfaQ (gene name)

Systematic name: ADP-L-glycero-β-D-manno-heptose:an α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] heptose^I 7-α-heptosyltransferase

Comments: The enzyme catalyses a glycosylation step in the biosynthesis of the inner core oligosaccharide of the lipopolysaccharide (endotoxin) of some Gram-negative bacteria.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Mudapaka, J. and Taylor, E.A. Cloning and characterization of the Escherichia coli heptosyltransferase III: Exploring substrate specificity in lipopolysaccharide core biosynthesis. FEBS Lett. 589 (2015) 1423-1429. [PMID: 25957775]

EC 2.4.99.26

Accepted name: O-antigen ligase

Reaction: a lipid-linked O antigen + a lipid A-core oligosaccharide = a lipopolysaccharide + a polyisoprenyl diphosphate

Other name(s): waaL (gene name); surface polymer:lipid A-core ligase; rfaL (gene name)

Systematic name: lipid-linked O-antigen:lipid A-core oligosaccharide O-antigen transferase (configuration-inverting)

Comments: This Gram-negative bacterial enzyme attaches the polymerized O antigen molecule to the outer core region of the lipid A-core oligosaccharide, finalizing the biosynthesis of the lipopolysaccharide. Prior to the reaction the two substrates are attached to the periplasmic-facing side of the inner membrane, and the enzyme transfers the O-antigen from its polyprenyl diphosphate membrane anchor (usually ditrans,octacis-undecaprenyl diphosphate) to a terminal sugar of the lipid A-core oligosaccharide. Despite the popular name "ligase", the enzyme is not a real ligase, as the reaction does not involve the hydrolysis of a phosphate bond in a triphosphate. The enzyme is embedded in the inner membrane and often has 12 trans-membrane segments. It is a metal-independent inverting glycosyltransferase, and in some cases it can attach surface polymers other than O-antigens to the lipid A-core oligosaccharide.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. MacLachlan, P.R., Kadam, S.K. and Sanderson, K.E. Cloning, characterization, and DNA sequence of the rfaLK region for lipopolysaccharide synthesis in Salmonella typhimurium LT2. J. Bacteriol. 173 (1991) 7151-7163. [PMID: 1657881]

2. Whitfield, C., Amor, P.A. and Koplin, R. Modulation of the surface architecture of gram-negative bacteria by the action of surface polymer:lipid A-core ligase and by determinants of polymer chain length. Mol. Microbiol. 23 (1997) 629-638. [PMID: 9157235]

3. Ruan, X., Loyola, D.E., Marolda, C.L., Perez-Donoso, J.M. and Valvano, M.A. The WaaL O-antigen lipopolysaccharide ligase has features in common with metal ion-independent inverting glycosyltransferases. Glycobiology 22 (2012) 288-299. [PMID: 21983211]

4. Ruan, X., Monjaras Feria, J., Hamad, M. and Valvano, M.A. Escherichia coli and Pseudomonas aeruginosa lipopolysaccharide O-antigen ligases share similar membrane topology and biochemical properties. Mol. Microbiol. 110 (2018) 95-113. [PMID: 30047569]

EC 2.4.99.27

Accepted name: O-antigen polymerase Wzy

Reaction: n lipid-linked O-antigen repeat units = a lipid-linked O antigen + (n–1) polyisoprenyl diphosphate

Other name(s): wzy (gene name); rfc (gene name); Wzy O-antigen polymerase; Wzy polymerase

Systematic name: lipid-linked O-antigen repeat unit:O-antigen O-antigen repeat-unit transferase

Comments: The Wzy-type polymerase polymerizes O antigen repeat unit oligosaccharides that are anchored to the periplasmic face of the inner membrane, forming an O antigen polysaccharide that is still anchored to the membrane. A Wzz chain length regulator (sometimes referred to as an O-antigen co-polymerase) normally interacts with Wzy to confer a distinctive modal chain length distribution. The resultant polysaccharide is transferred from the membrane anchor to the lipid A-core oligosaccharide by EC 2.4.99.26, O-antigen ligase, forming a complete lipopolysaccharide structure. There is an enormous diversity of O antigen polymerases with different specificities, reflecting the variability in the structure and composition of O-antigens.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Collins, L.V. and Hackett, J. Molecular cloning, characterization, and nucleotide sequence of the rfc gene, which encodes an O-antigen polymerase of Salmonella typhimurium. J. Bacteriol. 173 (1991) 2521-2529. [PMID: 1707412]

2. Woodward, R., Yi, W., Li, L., Zhao, G., Eguchi, H., Sridhar, P.R., Guo, H., Song, J.K., Motari, E., Cai, L., Kelleher, P., Liu, X., Han, W., Zhang, W., Ding, Y., Li, M. and Wang, P.G. In vitro bacterial polysaccharide biosynthesis: defining the functions of Wzy and Wzz. Nat. Chem. Biol. 6 (2010) 418-423. [PMID: 20418877]

3. Kenyon, J.J. and Reeves, P.R. The Wzy O-antigen polymerase of Yersinia pseudotuberculosis O:2a has a dependence on the Wzz chain-length determinant for efficient polymerization. FEMS Microbiol. Lett. 349 (2013) 163-170. [PMID: 24164168]

4. Islam, S.T., Huszczynski, S.M., Nugent, T., Gold, A.C. and Lam, J.S. Conserved-residue mutations in Wzy affect O-antigen polymerization and Wzz-mediated chain-length regulation in Pseudomonas aeruginosa PAO1. Sci. Rep. 3 (2013) 3441. [PMID: 24309320]

5. Islam, S.T. and Lam, J.S. Synthesis of bacterial polysaccharides via the Wzx/Wzy-dependent pathway. Can. J. Microbiol. 60 (2014) 697-716. [PMID: 25358682]

6. Nath, P. and Morona, R. Mutational analysis of the major periplasmic loops of Shigella flexneri Wzy: identification of the residues affecting O antigen modal chain length control, and Wzz-dependent polymerization activity. Microbiology (Reading) 161 (2015) 774-785. [PMID: 25627441]

7. Merino, S., Gonzalez, V. and Tomas, J.M. The first sugar of the repeat units is essential for the Wzy polymerase activity and elongation of the O-antigen lipopolysaccharide. Future Microbiol 11 (2016) 903-918. [PMID: 27357519]

EC 2.4.99.28

Accepted name: peptidoglycan glycosyltransferase

Reaction: [GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)]_n-diphosphoundecaprenol + GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)-diphosphoundecaprenol = [GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)]_n+1-diphosphoundecaprenol + undecaprenyl diphosphate

Glossary: Mur2Ac = N-acetylmuramic acid

Other name(s): PG-II; bactoprenyldiphospho-N-acetylmuramoyl-(N-acetyl-D-glucosaminyl)-pentapeptide:peptidoglycan N-acetylmuramoyl-N-acetyl-D-glucosaminyltransferase; penicillin binding protein (3 or 1B); peptidoglycan transglycosylase; undecaprenyldiphospho-(N-acetyl-D-glucosaminyl-(1→4)-N-acetyl-D-muramoylpentapeptide):undecaprenyldiphospho-(N-acetyl-D-glucosaminyl-(1→4)-N-acetyl-D-muramoylpentapeptide) disaccharidetransferase

Systematic name: [poly-N-acetyl-D-glucosaminyl-(1→4)-(N-acetyl-D-muramoylpentapeptide)]-diphosphoundecaprenol:[N-acetyl-D-glucosaminyl-(1→4)-N-acetyl-D-muramoylpentapeptide]-diphosphoundecaprenol disaccharidetransferase

Comments: The enzyme also works when the lysine residue is replaced by meso-2,6-diaminoheptanedioate (meso-2,6-diaminopimelate, A2pm) combined with adjacent residues through its L-centre, as it is in Gram-negative and some Gram-positive organisms. The undecaprenol involved is ditrans,octacis-undecaprenol (for definitions, click here). Involved in the synthesis of cell-wall peptidoglycan.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:

References:

1. Taku, A., Stuckey, M. and Fan, D.P. Purification of the peptidoglycan transglycosylase of Bacillus megaterium. J. Biol. Chem. 257 (1982) 5018-5022. [PMID: 6802846]

2. Goffin, C. and Ghuysen, J.-M. Multimodular penicillin-binding proteins: an enigmatic family of orthologs and paralogs. Microbiol. Mol. Biol. Rev. 62 (1998) 1079-1093. [PMID: 9841666]

3. van Heijenoort, J. Formation of the glycan chains in the synthesis of bacterial peptidoglycan. Glycobiology 11 (2001) 25. [PMID: 11320055]