Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (NC-IUBMB)

Proposed Changes to the Enzyme List

EC2 to EC6

The entries below are proposed additions and amendments to the Enzyme Nomenclature list. They were prepared for the NC-IUBMB by Keith Tipton, Sinéad Boyce, Gerry Moss, Dick Cammack and Hal Dixon, with assistance from Alan Chester, and were put on the web by Gerry Moss. Comments and suggestions on these draft entries should be sent to Professor K.F. Tipton and Dr S. Boyce (Department of Biochemistry, Trinity College Dublin, Dublin 2, Ireland). These entries were made public June 2003 and approved August 2003.

An asterisk before 'EC' indicates that this is an amendment to an existing enzyme rather than a new enzyme entry.


Contents

*EC 2.1.1.11 magnesium protoporphyrin IX methyltransferase
*EC 2.1.1.13 methionine synthase
*EC 2.1.1.14 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase
*EC 2.1.1.37 DNA (cytosine-5-)-methyltransferase
EC 2.1.1.73 Deleted.
EC 2.1.1.137 now EC 1.16.1.8
*EC 2.1.1.137 arsenite methyltransferase
EC 2.1.1.138 Deleted.
EC 2.1.1.148 thymidylate synthase (FAD)
EC 2.1.1.149 myricetin O-methyltransferase
EC 2.2.1.8 fluorothreonine transaldolase
EC 2.3.3.15 sulfoacetaldehyde acetyltransferase
*EC 2.4.1.13 sucrose synthase
*EC 2.4.1.140 alternansucrase
EC 2.4.1.169 now EC 2.4.2.39
EC 2.4.1.204 now EC 2.4.2.40
EC 2.4.1.229 [Skp1-protein]-hydroxyproline N-acetylglucosaminyltransferase
*EC 2.4.2.32 dolichyl-phosphate D-xylosyltransferase
EC 2.4.2.39 xyloglucan 6-xylosyltransferase
EC 2.4.2.40 zeatin O-β-D-xylosyltransferase
EC 2.5.1.58 protein farnesyltransferase
EC 2.5.1.59 protein geranylgeranyltransferase type I
EC 2.5.1.60 protein geranylgeranyltransferase type II
EC 2.5.1.61 hydroxymethylbilane synthase
EC 2.5.1.62 chlorophyll synthase
EC 2.5.1.63 adenosyl-fluoride synthase
*EC 2.6.1.55 taurine—2-oxoglutarate transaminase
EC 2.6.1.77 taurine—pyruvate aminotransferase
EC 2.8.3.15 succinyl-CoA:(R)-benzylsuccinate CoA-transferase
EC 2.8.3.16 formyl-CoA transferase
EC 2.8.3.17 cinnamoyl-CoA:phenyllactate CoA-transferase
EC 3.5.3.22 proclavaminate amidinohydrolase
EC 3.5.4.29 GTP cyclohydrolase IIa
*EC 4.1.1.39 ribulose-bisphosphate carboxylase
*EC 4.1.1.70 glutaconyl-CoA decarboxylase
EC 4.1.3.38 aminodeoxychorismate lyase
*EC 4.2.1.3 aconitate hydratase
EC 4.2.3.20 (R)-limonene synthase
EC 4.3.1.8 now EC 2.5.1.61
EC 4.4.1.12 Deleted.
EC 4.4.1.19 phosphosulfolactate synthase
*EC 5.4.3.4 D-lysine 5,6-aminomutase
*EC 5.4.3.5 D-ornithine 4,5-aminomutase
EC 5.4.4 Transferring hydroxy groups
EC 5.4.4.1 (hydroxyamino)benzene mutase
EC 5.4.4.2 isochorismate synthase
EC 5.4.99.6 now EC 5.4.4.2
EC 6.3.3.4 (carboxyethyl)arginine β-lactam-synthase
EC 6.3.5.8 aminodeoxychorismate synthase
EC 6.6 Forming nitrogen—metal bonds
EC 6.6.1 Forming coordination complexes
EC 6.6.1.1 magnesium chelatase

Entries

*EC 2.1.1.11

Common name: magnesium protoporphyrin IX methyltransferase

Reaction: S-adenosyl-L-methionine + magnesium protoporphyrin IX = S-adenosyl-L-homocysteine + magnesium protoporphyrin IX 13-methyl ester

For diagram of reaction click here (chlorophyll biosynthesis).

Other name(s): Mg-protoporphyrin IX methyltransferase; S-adenosylmethionine-magnesium protoporphyrin methyltransferase; magnesium-protoporphyrin O-methyltransferase; (-)-S-adenosyl-L-methionine:magnesium-protoporphyrin IX methyltransferase; S-adenosyl-L-methionine:Mg protoporphyrin methyltransferase; S-adenosylmethioninemagnesium protoporphyrin methyltransferase; S-adenosyl-L-methionine:magnesium-protoporphyrin O-methyltransferase

Systematic name: S-adenosyl-L-methionine:magnesium-protoporphyrin-IX O-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9029-82-7

References:

1. Gibson, K.D., Neuberger, A. and Tait, G.H. Studies on the biosynthesis of porphyrin and bacteriochlorophyll by Rhodopseudomonas spheroides. 4. S-Adenosylmethioninemagnesium protoporphyrin methyltransferase. Biochem. J. 88 (1963) 325-334.

2. Shepherd, M., Reid, J.D. and Hunter, C.N. Purification and kinetic characterisation of the magnesium protoporphyrin IX methyltransferase from Synechocystis PCC6803. Biochem. J. 371 (2003) 351-360. [PMID: 12489983]

3. Bollivar, D.W., Jiang, Z.Y., Bauer, C.E. and Beale, S.I. Heterologous expression of the bchM gene product from Rhodobacter capsulatus and demonstration that it encodes S-adenosyl-L-methionine:Mg-protoporphyrin IX methyltransferase. J. Bacteriol. 176 (1994) 5290-5296. [PMID: 8071204]

4. Gibson, L.C. and Hunter, C.N. The bacteriochlorophyll biosynthesis gene, bchM, of Rhodobacter sphaeroides encodes S-adenosyl-L-methionine: Mg protoporphyrin IX methyltransferase. FEBS Lett. 352 (1994) 127-130. [PMID: 7925960]

5. Ebbon, J.G. and Tait, G.H. Studies on S-adenosylmethionine-magnesium protoporphyrin methyltransferase in Euglena gracilis strain Z. Biochem. J. 111 (1969) 573-582. [PMID: 5774480]

[EC 2.1.1.11 created 1965, modified 2003]

*EC 2.1.1.13

Common name: methionine synthase

Reaction: 5-methyltetrahydrofolate + L-homocysteine = tetrahydrofolate + L-methionine

For diagram click here.

Other name(s): 5-methyltetrahydrofolate—homocysteine S-methyltransferase; 5-methyltetrahydrofolate—homocysteine transmethylase; N-methyltetrahydrofolate:L-homocysteine methyltransferase; N5-methyltetrahydrofolate methyltransferase; N5-methyltetrahydrofolate—homocysteine cobalamin methyltransferase; N5-methyltetrahydrofolic—homocysteine vitamin B12 transmethylase; B12 N5-methyltetrahydrofolate homocysteine methyltransferase; methionine synthetase; methyltetrahydrofolate—homocysteine vitamin B12 methyltransferase; tetrahydrofolate methyltransferase; tetrahydropteroylglutamate methyltransferase; tetrahydropteroylglutamic methyltransferase; vitamin B12 methyltransferase; cobalamin-dependent methionine synthase; methionine synthase (cobalamin-dependent); MetH

Systematic name: 5-methyltetrahydrofolate:L-homocysteine S-methyltransferase

Comments: Contains zinc and cobamide. The enzyme becomes inactivated occasionally during its cycle by oxidation of Co(I) to Co(II). Reactivation by reductive methylation is catalysed by the enzyme itself, with S-adenosyl-L-methionine as the methyl donor and a reducing system. For the mammalian enzyme, the reducing system involves NADPH and EC 1.16.1.8, [methionine synthase] reductase. In bacteria, the reducing agent is flavodoxin, and no further catalyst is needed (the flavodoxin is kept in the reduced state by NADPH and EC 1.18.1.2, ferredoxin—NADP+ reductase). Acts on the monoglutamate as well as the triglutamate folate, in contrast with EC 2.1.1.14, 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase, which acts only on the triglutamate.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9030-23-2

References:

1. Burton, E.G. and Sakami, W. The formation of methionine from the monoglutamate form of methyltetrahydrofolate by higher plants. Biochem. Biophys. Res. Commun. 36 (1969) 228-234. [PMID: 5799642]

2. Foster, M.A., Dilworth, M.J. and Woods, D.D. Cobalamin and the synthesis of methionine by Escherichia coli. Nature 201 (1964) 39-42.

3. Guest, J.R., Friedman, S., Foster, M.A., Tejerina, G. and Woods, D.D. Transfer of the methyl group from N5-methyltetrahydrofolates to homocysteine in Escherichia coli. Biochem. J. 92 (1964) 497-504.

4. Loughlin, R.E., Elford, H.L. and Buchanan, J.M. Enzymatic synthesis of the methyl group of methionine. VII. Isolation of a cobalamin-containing transmethylase (5-methyltetrahydro-folate-homocysteine) from mammalian liver. J. Biol. Chem. 239 (1964) 2888-2895.

5. Taylor, R.T. Escherichia coli B N5-methyltetrahydrofolate-homocysteine cobalamin methyltransferase: gel-filtration behavior of apoenzyme and holoenzymes. Biochim. Biophys. Acta 242 (1971) 355-364. [PMID: 4946148]

6. Jarrett, J.T., Huang, S. and Matthews, R.G. Methionine synthase exists in two distinct conformations that differ in reactivity toward methyltetrahydrofolate, adenosylmethionine, and flavodoxin. Biochemistry 37 (1998) 5372-5382. [PMID: 9548919]

7. Peariso, K., Goulding, C.W., Huang, S., Matthews, R.G. and Penner-Hahn, J.E. Characterization of the zinc binding site in methionine synthase enzymes of Escherichia coli: The role of zinc in the methylation of homocysteine. J. Am. Chem. Soc. 120 (1998) 8410-8416.

8. Hall, D.A., Jordan-Starck, T.C., Loo, R.O., Ludwig, M.L. and Matthews, R.G. Interaction of flavodoxin with cobalamin-dependent methionine synthase. Biochemistry 39 (2000) 10711-10719. [PMID: 10978155]

9. Bandarian, V., Pattridge, K.A., Lennon, B.W., Huddler, D.P., Matthews, R.G. and Ludwig, M.L. Domain alternation switches B12-dependent methionine synthase to the activation conformation. Nat. Struct. Biol. 9 (2002) 53-56. [PMID: 11731805]

[EC 2.1.1.13 created 1972, modified 2003]

*EC 2.1.1.14

Common name: 5-methyltetrahydropteroyltriglutamate—homocysteine S-methyltransferase

Reaction: 5-methyltetrahydropteroyltri-L-glutamate + L-homocysteine = tetrahydropteroyltri-L-glutamate + L-methionine

Other name(s): tetrahydropteroyltriglutamate methyltransferase; homocysteine methylase; methyltransferase, tetrahydropteroylglutamate-homocysteine transmethylase; methyltetrahydropteroylpolyglutamate:homocysteine methyltransferase; cobalamin-independent methionine synthase; methionine synthase (cobalamin-independent); MetE

Systematic name: 5-methyltetrahydropteroyltri-L-glutamate:L-homocysteine S-methyltransferase

Comments: Requires phosphate and contains zinc. The enzyme from E. coli also requires a reducing system. Unlike EC 2.1.1.13, methionine synthase, this enzyme does not contain cobalamin.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9068-29-5

References:

1. Guest, J.R., Friedman, S., Foster, M.A., Tejerina, G. and Woods, D.D. Transfer of the methy grouup from N5-methyltetrahydrofolates to homocysteine in Escherichia coli. Biochem. J. 92 (1964) 497-504.

2. Whitfield, C.D., Steers, E.J., Jr. and Weissbach, H. Purification and properties of 5-methyltetrahydropteroyltriglutamate-homocysteine transmethylase. J. Biol. Chem. 245 (1970) 390-401. [PMID: 4904482]

3. Eichel, J., Gonzalez, J.C., Hotze, M., Matthews, R.G. and Schroder, J. Vitamin B12-independent methionine synthase from a higher-plant (Catharanthus roseus) - molecular characterization, regulation, heterologous expression, and enzyme properties. Eur. J. Biochem. 230 (1995) 1053-1058. [PMID: 7601135]

4. Gonzalez, J.C., Peariso, K., PennerHahn, J.E. and Matthews, R.G. Cobalamin-independent methionine synthase from Escherichia coli: A zinc metalloenzyme. Biochemistry 35 (1996) 12228-12234. [PMID: 8823155]

5. Peariso, K., Goulding, C.W., Huang, S., Matthews, R.G. and Penner-Hahn, J.E. Characterization of the zinc binding site in methionine synthase enzymes of Escherichia coli: The role of zinc in the methylation of homocysteine. J. Am. Chem. Soc. 120 (1998) 8410-8416.

[EC 2.1.1.14 created 1972, modified 2003]

*EC 2.1.1.37

Common name: DNA (cytosine-5-)-methyltransferase

Reaction: S-adenosyl-L-methionine + DNA = S-adenosyl-L-homocysteine + DNA containing 5-methylcytosine

Other name(s): EcoRI methylase; DNA 5-cytosine methylase; DNA cytosine c5 methylase; DNA cytosine methylase; DNA methylase; DNA methyltransferase; DNA transmethylase; DNA-cytosine 5-methylase; DNA-cytosine methyltransferase; HpaII methylase; HpaII' methylase; M.BsuRIa; M.BsuRIb; Type II DNA methylase; cytosine 5-methyltransferase; cytosine DNA methylase; cytosine DNA methyltransferase; cytosine-specific DNA methyltransferase; deoxyribonucleate methylase; deoxyribonucleate methyltransferase; deoxyribonucleic (cytosine-5-)-methyltransferase; deoxyribonucleic acid (cytosine-5-)-methyltransferase; deoxyribonucleic acid methylase; deoxyribonucleic acid methyltransferase; deoxyribonucleic acid modification methylase; deoxyribonucleic methylase; methylphosphotriester-DNA methyltransferase; modification methylase; restriction-modification system; site-specific DNA-methyltransferase (cytosine-specific)

Systematic name: S-adenosyl-L-methionine:DNA (cytosine-5-)-methyltransferase

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9037-42-7

References:

1. Gold, M. and Hurwitz, J. The enzymatic methylation of ribonucleic acid and deoxyribonucleic acid. V. Purification and properties of the deoxyribonucleic acid-methylating activity of Escherichia coli. J. Biol. Chem. 239 (1964) 3858-2865.

2. Kalousek, F. and Morris, N.R. The purification and properties of deoxyribonucleic acid methylase from rat spleen. J. Biol. Chem. 244 (1969) 1157-1163. [PMID: 4975067]

3. Roy, P.H. and Weissbach, A. DNA methylase from HeLa cell nuclei. Nucleic Acids Res. 2 (1975) 1669-1684. [PMID: 1187340]

4. Simon, D., Grunert, F., Acken, U.Y., Döring, H.P. and Kröger, H. DNA-methylase from regenerating rat liver: purification and characterisation. Nucleic Acids Res. 5 (1978) 2153-2167. [PMID: 673848]

5. Sneider, T.W., Teague, W.M. and Rogachewsky, L.M. S-Adenosylmethionine: DNA-cytosine 5-methyltransferase from a Novikoff rat hepatoma cell line. Nucleic Acids Res. 2 (1975) 1685-1700. [PMID: 171625]

6. Turnbull, J.F. and Adams, R.L.P. DNA methylase: purification from ascites cells and the effect of various DNA substrates on its activity. Nucleic Acids Res. 3 (1976) 677-695. [PMID: 131936]

7. Kessler, C. and Manta, V. Specificity of restriction endonucleases and DNA modification methyltransferases: a review. Gene 92 (1990) 1-248. [PMID: 91032997]

8. Roberts, R.J. Restriction enzymes and their isoschizomers. Nucleic Acids Res. 18 (1990) 2331-2365. [PMID: 2159140]

9. Yuan, R. Structure and mechanism of multifunctional restriction endonucleases. Annu. Rev. Biochem. 50 (1981) 285-319. [PMID: 6267988]

[EC 2.1.1.37 created 1972, (EC 2.1.1.73 incorporated 2003), modified 2003]

[EC 2.1.1.73 Deleted entry: site-specific DNA-methyltransferase (cytosine-specific). Reaction is that of EC 2.1.1.37, DNA (cytosine-5-)-methyltransferase. (EC 2.1.1.73 created 1984, deleted 2003)]

*EC 2.1.1.137

Common name: arsenite methyltransferase

Reaction: (1) S-adenosyl-L-methionine + arsenite = S-adenosyl-L-homocysteine + methylarsonate

(2) S-adenosyl-L-methionine + methylarsonite = S-adenosyl-L-homocysteine + dimethylarsinate

For diagram click here.

Other name(s): S-adenosyl-L-methionine:arsenic(III) methyltransferase; S-adenosyl-L-methionine:methylarsonite As-methyltransferase; methylarsonite methyltransferase

Systematic name: S-adenosyl-L-methionine:arsenite As-methyltransferase

Comments: An enzyme of the biotransformation pathway that forms dimethylarsinate from inorganic arsenite and arsenate. It methylates arsenite to form methylarsonate, Me-AsO3H2, which is reduced by EC 1.20.4.2, methylarsonate reductase, to methylarsonite, Me-As(OH)2. Methylarsonite is also a substrate for this enzyme (EC 2.1.1.137), which converts it into the much less toxic compound dimethylarsinate (cacodylate), Me2As(O)-OH.

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

References:

1. Zakharyan, R.A. and Aposhian, H.V. Enzymatic reduction of arsenic compounds in mammalian systems: The rate-limiting enzyme of rabbit liver arsenic biotransformation is MMA(V) reductase. Chem. Res. Toxicol. 121 (1999) 1278-1283. [PMID: 10604879]

2. Zakharyan, R.A., Ayala-Fierro, F., Cullen, W.R., Carter, D.M. and Aposhian, H.V. Enzymatic methylation of arsenic compounds. VII. Monomethylarsonous acid (MMAIII) is the substrate for MMA methyltransferase of rabbit liver and human hepatocytes. Toxicol. Appl. Pharmacol. 158 (1999) 9-15. [PMID: 10387927]

3. Zakharyan, R.A., Wildfang, E. and Aposhian, H.V. Enzymatic methylation of arsenic compounds. III. The marmoset and tamarin, but not the rhesus, monkeys are deficient in methyltransferases that methylate inorganic arsenic. Toxicol. Appl. Pharmacol. 140 (1996) 77-84. [PMID: 8806872]

4. Zakharyan, R.A., Wu, Y., Bogdan, G.M. and Aposhian, H.V. Enzymatic methylation of arsenic compounds: assay, partial purification, and properties of arsenite methyltransferase and monomethylarsonic acid methyltransferase of rabbit liver. Chem. Res. Toxicol. 8 (1995) 1029-1038. [PMID: 8605285]

5. Lin, S., Shi, Q., Nix, F.B., Styblo, M., Beck, M.A., Herbin-Davis, K.M., Hall, L.L., Simeonsson, J.B. and Thomas, D.J. A novel S-adenosyl-L-methionine:arsenic(III) methyltransferase from rat liver cytosol. J. Biol. Chem. 277 (2002) 10795-10803. [PMID: 11790780]

[EC 2.1.1.137 created 2000, (EC 2.1.1.138 incorporated 2003), modified 2003]

[EC 2.1.1.138 Deleted entry: methylarsonite methyltransferase. Reaction due to EC 2.1.1.137, methylarsonite methyltransferase. (EC 2.1.1.138 created 2000, deleted 2003)]

EC 2.1.1.148

Common name: thymidylate synthase (FAD)

Reaction: 5,10-methylenetetrahydrofolate + dUMP + FADH2 = dTMP + tetrahydrofolate + FAD

Other name(s): Thy1; ThyX

Systematic name: 5,10-methylenetetrahydrofolate,FADH2:dUMP C-methyltransferase

Comments: FMN can replace FAD. Reaction shown is distinct from that of the classical thymidylate synthase, ThyA (EC 2.1.1.45).

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

References:

1. Myllykallio, H., Lipowski, G., Leduc, D., Filee, J., Forterre, P. and Liebl, U. An alternative flavin-dependent mechanism for thymidylate synthesis. Science 297 (2002) 105-107. [PMID: 12029065]

[EC 2.1.1.148 created 2003]

EC 2.1.1.149

Common name: myricetin O-methyltransferase

Reaction: 2 S-adenosyl-L-methionine + myricetin = 2 S-adenosyl-L-homocysteine + syringetin

For diagram of reaction, click here.

Glossary: syringetin: 4',5,7-trihydroxy-3',5'-dimethoxyflavan-4-one

Other name(s): CrCOMT2; flavonoid 3',5'-O-dimethyltransferase

Systematic name:S-adenosyl-L-methionine:myricetin O-methyltransferase

Comments: The enzyme from Catharanthus roseus (Madagascar periwinkle) is unusual as it carries out two methylations of the same substrate. Also catalyses the methylation of dihydromyricetin.

References:

1. Cacace, S., Schröder, G., Wehinger, E., Strack, D., Schmidt, J. and Schröder, J. A flavonol O-methyltransferase from Catharanthus roseus performing two sequential methylations. Phytochemistry 62 (2003) 127-137. [PMID: 12482447]

[EC 2.1.1.149 created 2003]

EC 2.2.1.8

Common name: fluorothreonine transaldolase

Reaction: L-threonine + fluoroacetaldehyde = acetaldehyde + 4-fluoro-L-threonine

Systematic name: fluoroacetaldehyde:L-threonine aldehydetransferase

Comments: A pyridoxal phosphate protein. Can also convert chloroacetaldehyde into 4-chloro-L-threonine. Unlike EC 2.1.2.1, glycine hydroxymethyltransferase, does not use glycine as a substrate.

References:

1. Murphy, C.D., O'Hagan, D. and Schaffrath, C. Identification of a PLP-dependent threonine transaldolase: a novel enzyme involved in 4-fluorothreonine biosynthesis in Streptomyces cattleya. Angew. Chem. Int. Ed. Engl. 40 (2001) 4479-4481. [PMID: 12404452]

2. Murphy, C.D., Schaffrath, C. and O'Hagan, D. Fluorinated natural products: the biosynthesis of fluoroacetate and 4-fluorothreonine in Streptomyces cattleya. Chemosphere 52 (2003) 455-461. [PMID: 12738270]

[EC 2.2.1.8 created 2003]

EC 2.3.3.15

Common name: sulfoacetaldehyde acetyltransferase

Reaction: acetyl phosphate + sulfite = 2-sulfoacetaldehyde + phosphate

Systematic name: acetyl-phosphate:sulfite S-acetyltransferase (acyl-phosphate hydrolysing, 2-oxoethyl-forming)

Comments: Requires Mg2+.

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

References:

1. Ruff, J, Denger, K. and Cook, A.M. Sulphoacetaldehyde acetyltransferase yields acetyl phosphate: purification from Alcaligenes defragrans and gene clusters in taurine degradation. Biochem. J. 369 (2003) 275-285. [PMID: 12358600]

[EC 2.3.3.15 created 2003]

*EC 2.4.1.13

Common name: sucrose synthase

Reaction: NDP-glucose + D-fructose = NDP + sucrose

Other name(s): UDPglucose-fructose glucosyltransferase; sucrose synthetase; sucrose-UDP glucosyltransferase; sucrose-uridine diphosphate glucosyltransferase; uridine diphosphoglucose-fructose glucosyltransferase

Systematic name: NDP-glucose:D-fructose 2-α-D-glucosyltransferase

Comments: Although UDP is generally considered to be the preferred nucleoside diphosphate for sucrose synthase, numerous studies have shown that ADP serves as an effective acceptor molecule to produce ADP-glucose [3-9]. Sucrose synthase has a dual role in producing both UDP-glucose (necessary for cell wall and glycoprotein biosynthesis) and ADP-glucose (necessary for starch biosynthesis) [10].

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 9030-05-1

References:

1. Avigad, G. and Milner, Y. UDP-glucose:fructose transglucosylase from sugar beet roots. Methods Enzymol. 8 (1966) 341-345.

2. Cardini, C.E., Leloir, L.F. and Chiriboga, J. The biosynthesis of sucrose. J. Biol. Chem. 214 (1955) 149-155.

3. Delmer, D.P. The purification and properties of sucrose synthetase from etiolated Phaseolus aureus seedlings. J. Biol. Chem. 247 (1972) 3822-3828. [PMID: 4624446]

4. Murata, T., Sugiyama, T., Minamikawa, T. and Akazawa, T. Enzymic mechanism of starch synthesis in ripening rice grains. Mechanism of the sucrose-starch conversion. Arch. Biochem. Biophys. 113 (1966) 34-44. [PMID: 5941994]

5. Nakai, T., Konishi, T., Zhang, X.-Q., Chollet, R., Tonouchi, N., Tsuchida, T., Yoshinaga, F., Mori, H., Sakai, F. and Hayashi, T. An increase in apparent affinity for sucrose of mung bean sucrose synthase is caused by in vitro phosphorylation or directed mutagenesis of Ser11. Plant Cell Physiol. 39 (1998) 1337-1341. [PMID: 10050318]

6. Porchia, A.C., Curatti, L. and Salerno, G.L. Sucrose metabolism in cyanobacteria: sucrose synthase from Anabaena sp. strain PCC 7119 is remarkably different from the plant enzymes with respect to substrate affinity and amino-terminal sequence. Planta 210 (1999) 34-40. [PMID: 10592030]

7. Ross, H.A. and Davies, H.V. Purification and characterization of sucrose synthase from the cotyledons of Vicia fava L. Plant Physiol. 100 (1992) 1008-1013.

8. Silvius, J.E. and Snyder, F.W. Comparative enzymic studies of sucrose metabolism in the taproots and fibrous roots of Beta vulgaris L. Plant Physiol. 64 (1979) 1070-1073.

9. Tanase, K. and Yamaki, S. Purification and characterization of two sucrose synthase isoforms from Japanese pear fruit. Plant Cell Physiol. 41 (2000) 408-414. [PMID: 10845453]

10. Baroja-Fernández, E., Muñoz, F.J., Saikusa, T., Rodríguez-López, M., Akazawa, T. and Pozueta-Romero, J. Sucrose synthase catalyzes the de novo production of ADPglucose linked to starch biosynthesis in heterotrophic tissues of plants. Plant Cell Physiol. 44 (2003) 500-509. [PMID: 12773636]

[EC 2.4.1.13 created 1961, modified 2003]

*EC 2.4.1.140

Common name: alternansucrase

Reaction: Transfers alternately an α-D-glucosyl residue from sucrose to the 6-position and the 3-position of the non-reducing terminal residue of an α-D-glucan, thus producing a glucan having alternating α-1,6- and α-1,3-linkages

Other name(s): sucrose-1,6(3)-α-glucan 6(3)-α-glucosyltransferase; sucrose:1,6-, 1,3-α-D-glucan 3-α- and 6-α-D-glucosyltransferase

Systematic name: sucrose:1,6(1,3)-α-D-glucan 6(3)-α-D-glucosyltransferase

Comments: The product, which has quite different properties from other dextrans, has been called alternan.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 100630-46-4

References:

1. Cote, G.L. and Robyt, J.F. Isolation and partial characterization of an extracellular glucansucrase from Leuconostoc mesenteroides NRRL B-1355 that synthesizes an alternating (1→6), (1→3)-α-D-glucan. Carbohydr. Res. 101 (1982) 57-74. [PMID: 7060056]

[EC 2.4.1.140 created 1984, modified 2003]

[EC 2.4.1.169 Transferred entry: now EC 2.4.2.39, xyloglucan 6-xylosyltransferase (EC 2.4.1.169 created 1989, deleted 2003)]

[EC 2.4.1.204 Transferred entry: now EC 2.4.2.40, zeatin O-β-D-xylosyltransferase (EC 2.4.1.204 created 1992, deleted 2003)]

EC 2.4.1.229

Common name: [Skp1-protein]-hydroxyproline N-acetylglucosaminyltransferase

Reaction: UDP-N-acetylglucosamine + [Skp1-protein]-hydroxyproline = UDP + [Skp1-protein]-O-(N-acetyl-D-glucosaminyl)hydroxyproline

Other name(s): Skp1-HyPro GlcNAc-transferase; UDP-N-acetylglucosamine (GlcNAc):hydroxyproline polypeptide GlcNAc-transferase; UDP-GlcNAc:Skp1-hydroxyproline GlcNAc-transferase; UDP-GlcNAc:hydroxyproline polypeptide GlcNAc-transferase

Systematic name: UDP-N-acetyl-D-glucosamine:[Skp1-protein]-hydroxyproline N-acetyl-D-glucosaminyl-transferase

Comments: Requires dithiothreitol and a divalent cation for activity. This enzyme commences the building up of a pentasaccharide (Galα1-6Galα1-L-Fucα1-2Galβ1-3GlcNAc) on Hyp-143 of the Dictyostelium protein Skp1, which is required for the ubiquitination of cell-cycle regulatory proteins and transcription factors. The fucose residue is probably in the α configuration [3]. The specificity of the enzyme for Skp1-Hyp-143 and its high affinity for this substrate suggests that it is the GlcNAc-transferase that modifies Skp1 in vivo.

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

References:

1. van der Wel, H.,Morris, H.R., Panico, M., Paxton, T., Dell, A., Kaplan, L. and West, C.M. Molecular cloning and expression of a UDP-N-acetylglucosamine (GlcNAc):hydroxyproline polypeptide GlcNAc-transferase that modifies Skp1 in the cytoplasm of Dictyostelium. J. Biol. Chem. 277 (2002) 46328-46337. [PMID: 12244115]

2. Teng-umnuay, P., van der Wel, H. and West, C.M. Identification of a UDP-GlcNAc:Skp1-hydroxyproline GlcNAc-transferase in the cytoplasm of Dictyostelium. J. Biol. Chem. 274 (1999) 36392-36402. [PMID: 10593934]

3. West, C.M., van der Wel, H. and Gaucher, E.A. Complex glycosylation of Skp1 in Dictyostelium: implications for the modification of other eukaryotic cytoplasmic and nuclear proteins. Glycobiology 12 (2002) 17R-27R. [PMID: 11886837]

[EC 2.4.1.229 created 2003]

*EC 2.4.2.32

Common name: dolichyl-phosphate D-xylosyltransferase

Reaction: UDP-D-xylose + dolichyl phosphate = UDP + dolichyl D-xylosyl phosphate

Glossary: dolichol

Systematic name: UDP-D-xylose:dolichyl-phosphate D-xylosyltransferase

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

References:

1. Waechter, C.J., Lucas, J.J. and Lennarz, W.J. Evidence for xylosyl lipids as intermediates in xylosyl transfers in hen oviduct membranes. Biochem. Biophys. Res. Commun. 56 (1974) 343-350. [PMID: 4823870]

[EC 2.4.2.32 created 1984, modified 2003]

EC 2.4.2.39

Common name: xyloglucan 6-xylosyltransferase

Reaction: Transfers an α-D-xylosyl residue from UDP-D-xylose to a glucose residue in xyloglucan, forming an α-1,6-D-xylosyl-D-glucose linkage

Other name(s): uridine diphosphoxylose-xyloglucan 6α-xylosyltransferase; xyloglucan 6-α-D-xylosyltransferase

Systematic name: UDP-D-xylose:xyloglucan 1,6-α-D-xylosyltransferase

Comments: In association with EC 2.4.1.168 (xyloglucan 4-glucosyltransferase), this enzyme brings about the synthesis of xyloglucan; concurrent transfers of glucose and xylose are necessary for this synthesis.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 80238-01-3

References:

1. Hayashi, T. and Matsuda, K. Biosynthesis of xyloglucan in suspension-cultured soybean cells. Occurrence and some properties of xyloglucan 4-β-D-glucosyltransferase and 6-α-D-xylosyltransferase. J. Biol. Chem. 256 (1981) 11117-11122. [PMID: 6457048]

2. Hayashi, T. and Matsuda, K. Biosynthesis of xyloglucan in suspension-cultured soybean cells-synthesis of xyloglucan from UDP-glucose and UDP-xylose in the cell-free system. Plant Cell Physiol. 22 (1981) 517-523.

[EC 2.4.2.39 created 1989 as EC 2.4.1.169, transferred 2003 to EC 2.4.2.39]

EC 2.4.2.40

Common name: zeatin O-β-D-xylosyltransferase

Reaction: UDP-D-xylose + zeatin = UDP + O-β-D-xylosylzeatin

Glossary: zeatin

Other name(s): uridine diphosphoxylose-zeatin xylosyltransferase; zeatin O-xylosyltransferase

Systematic name: UDP-D-xylose:zeatin O-β-D-xylosyltransferase

Comments: Does not act on UDP-glucose (cf. EC 2.4.1.103 alizarin 2-β-glucosyltransferase).

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 110541-22-5

References:

1. Turner, J.E., Mok, D.W.S., Mok, M.C. and Shaw, G. Isolation and partial-purification of an enzyme catalyzing the formation of O-xylosylzeatin in Phaseolus vulgaris embryos. Proc. Natl Acad. Sci. USA 84 (1987) 3714-3717.

[EC 2.4.2.40 created 1992 as EC 2.4.1.204, transferred 2003 to EC 2.4.2.40]

EC 2.5.1.58

Common name: protein farnesyltransferase

Reaction: farnesyl diphosphate + protein-cysteine = S-farnesyl protein + diphosphate

Other name(s): FTase

Systematic name: farnesyl-diphosphate:protein-cysteine farnesyltransferase

Comments: This enzyme, along with geranylgeranyltransferase types I (EC 2.5.1.59) and II (EC 2.5.1.60), constitutes the protein prenyltransferase family of enzymes. Catalyses the formation of a thioether linkage between the C-1 of an isoprenyl group and a cysteine residue fourth from the C-terminus of the protein. These protein acceptors have the C-terminal sequence CA1A2X, where the terminal residue, X, is preferably serine, methionine, alanine or glutamine; leucine makes the protein a substrate for EC 2.5.1.59. The enzymes are relaxed in specificity for A1, but cannot act if A2 is aromatic. Substrates of the prenyltransferases include Ras, Rho, Rab, other Ras-related small GTP-binding proteins, γ-subunits of heterotrimeric G-proteins, nuclear lamins, centromeric proteins and many proteins involved in visual signal transduction. A zinc metalloenzyme that requires Mg2+ for activity.

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

References:

1. Furfine, E.S., Leban, J.J., Landavazo, A., Moomaw, J.F. and Casey, P.J. Protein farnesyltransferase: kinetics of farnesyl pyrophosphate binding and product release. Biochemistry 34 (1995) 6857-6862. [PMID: 7756316]

2. Casey, P.J. and Seabra, M.C. Protein prenyltransferases. J. Biol. Chem. 271 (1996) 5289-5292. [PMID: 8621375]

3. Long, S.B., Casey, P.J. and Beese, L.S. Cocrystal structure of protein farnesyltransferase complexed with a farnesyl diphosphate substrate. Biochemistry 37 (1998) 9612-9618. [PMID: 9657673]

4. Micali, E., Chehade, K.A., Isaacs, R.J., Andres, D.A. and Spielmann, H.P. Protein farnesyltransferase isoprenoid substrate discrimination is dependent on isoprene double bonds and branched methyl groups. Biochemistry 40 (2001) 12254-12265. [PMID: 11591144]

5. Long, S.B., Casey, P.J. and Beese, L.S. Reaction path of protein farnesyltransferase at atomic resolution. Nature 419 (2002) 645-650. [PMID: 12374986]

6. Gibbs, R.A. Prenyl transfer and the enzymes of terpenoid and steroid biosynthesis. In: Sinnott, M. (Ed.), Comprehensive Biological Catalysis. A Mechanistic Reference., vol. 1, Academic Press, San Diego, CA, 1998, pp. 31-118.

[EC 2.5.1.58 created 2003]

EC 2.5.1.59

Common name: protein geranylgeranyltransferase type I

Reaction: geranylgeranyl diphosphate + protein-cysteine = S-geranylgeranyl-protein + diphosphate

Other name(s): GGTase-I; GGTaseI

Systematic name: geranylgeranyl-diphosphate:protein-cysteine geranyltransferase

Comments: This enzyme, along with protein farnesyltransferase (EC 2.5.1.58) and protein geranylgeranyltransferase type II (EC 2.5.1.60), constitutes the protein prenyltransferase family of enzymes. Catalyses the formation of a thioether linkage between the C-1 atom of the geranylgeranyl group and a cysteine residue fourth from the C-terminus of the protein. These protein acceptors have the C-terminal sequence CA1A2X, where the terminal residue, X, is preferably leucine; serine, methionine, alanine or glutamine makes the protein a substrate for EC 2.5.1.58. The enzymes are relaxed in specificity for A1, but cannot act if A2 is aromatic. Known targets of this enzyme include most γ-subunits of heterotrimeric G proteins and Ras-related GTPases such as members of the Ras and Rac/Rho families. A zinc metalloenzyme. The Zn2+ is required for peptide, but not for isoprenoid, substrate binding.

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

References:

1. Casey, P.J. and Seabra, M.C. Protein prenyltransferases. J. Biol. Chem. 271 (1996) 5289-5292. [PMID: 8621375]

2. Zhang, F.L. and Casey, P.J. Influence of metal ions on substrate binding and catalytic activity of mammalian protein geranylgeranyltransferase type-I. Biochem. J. 320 (1996) 925-932. [PMID: 9003382]

3. Gibbs, R.A. Prenyl transfer and the enzymes of terpenoid and steroid biosynthesis. In: Sinnott, M. (Ed.), Comprehensive Biological Catalysis. A Mechanistic Reference., vol. 1, Academic Press, San Diego, 1998, pp. 31-118.

[EC 2.5.1.59 created 2003]

EC 2.5.1.60

Common name: protein geranylgeranyltransferase type II

Reaction: 2 geranylgeranyl diphosphate + protein-cysteine = 2 S-geranylgeranyl-protein + 2 diphosphate

Other name(s): GGTaseII; Rab geranylgeranyltransferase; RabGGTase

Systematic name: geranylgeranyl-diphosphate,geranylgeranyl-diphosphate:protein-cysteine geranyltransferase

Comments: This enzyme, along with protein farnesyltransferase (EC 2.5.1.58) and protein geranylgeranyltransferase type I (EC 2.5.1.59), constitutes the protein prenyltransferase family of enzymes. Attaches geranylgeranyl groups to two C-terminal cysteines in Ras-related GTPases of a single family, the Rab family (Ypt/Sec4 in lower eukaryotes) that terminate in XXCC, XCXC and CCXX motifs. Reaction is entirely dependent on the Rab substrate being bound to Rab escort protein (REP).

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

References:

1. Casey, P.J. and Seabra, M.C. Protein prenyltransferases. J. Biol. Chem. 271 (1996) 5289-5292. [PMID: 8621375]

2. Wilson, A.L., Erdman, R.A., Castellano, F. and Maltese, W.A. Prenylation of Rab8 GTPase by type I and type II geranylgeranyl transferases. Biochem. J. 333 (1998) 497-504. [PMID: 9677305]

3. Zhang, H., Seabra, M.C. and Deisenhofer, J. Crystal structure of Rab geranylgeranyltransferase at 2.0 Å resolution. Structure Fold. Des. 8 (2000) 241-251. [PMID: 10745007]

4. Thomä, N.H., Niculae, A., Goody, R.S. and Alexandrov, K. Double prenylation by RabGGTase can proceed without dissociation of the mono-prenylated intermediate. J. Biol. Chem. 276 (2001) 48631-48636. [PMID: 11591706]

5. Rak, A., Niculae, A., Kalinin, A., Thomä, N.H., Sidorovitch, V., Goody, R.S. and Alexandrov, K. In vitro assembly, purification, and crystallization of the Rab geranylgeranyl transferase:substrate complex. Protein Expr. Purif. 25 (2002) 23-30. [PMID: 12071695]

6. Gibbs, R.A. Prenyl transfer and the enzymes of terpenoid and steroid biosynthesis. In: Sinnott, M. (Ed.), Comprehensive Biological Catalysis. A Mechanistic Reference., vol. 1, Academic Press, San Diego, CA, 1998, pp. 31-118.

[EC 2.5.1.60 created 2003]

EC 2.5.1.61

Common name: hydroxymethylbilane synthase

Reaction: 4 porphobilinogen + H2O = hydroxymethylbilane + 4 NH3

For diagram click here.

Other name(s): HMB-synthase; porphobilinogen deaminase; pre-uroporphyrinogen synthase; uroporphyrinogen I synthase; uroporphyrinogen I synthetase; uroporphyrinogen synthase; uroporphyrinogen synthetase

Systematic name: porphobilinogen ammonia-lyase (polymerizing)

Comments: The enzyme works by stepwise addition of pyrrolylmethyl groups until a hexapyrrole is present at the active centre. The terminal tetrapyrrole is then hydrolysed to yield the product, leaving a cysteine-bound dipyrrole on which assembly continues. In the presence of a second enzyme, EC 4.2.1.75 uroporphyrinogen-III synthase, which is often called cosynthase, the product is cyclized to form uroporphyrinogen-III. If EC 4.2.1.75 is absent, the hydroxymethylbilane cyclizes spontaneously to form uroporphyrinogen I.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9074-91-3

References:

1. Battersby, A.R., Fookes, C.J.R., Matcham, G.W.J. and McDonald, E. Biosynthesis of the pigments of life: formation of the macrocycle. Nature 285 (1980) 17-21. [PMID: 6769048]

2. Frydman, R.B. and Feinstein, G. Studies on porphobilinogen deaminase and uroporphyrinogen 3 cosynthase from human erythrocytes. Biochim. Biophys. Acta 350 (1974) 358-373. [PMID: 4847568]

3. Levin, E.Y. and Coleman, D.L. The enzymatic conversion of porphobilinogen to uroporphyrinogen catalyzed by extracts of hematopoietic mouse spleen. J. Biol. Chem. 242 (1967) 4247-4253. [PMID: 6061709]

4. Warren, M.J. and Jordan P.M. Investigation into the nature of substrate binding to the dipyrromethane cofactor of Escherichia coli porphobilinogen deaminase. Biochemistry 27 (1988) 9020-9030. [PMID: 3069132]

5. Miller, A.D., Hart, G.J., Packman, L.C. and Battersby, A.R. Evidence that the pyrromethane cofactor of hydroxymethylbilane synthase (porphobilinogen deaminase) is bound to the protein through the sulphur atom of cysteine-242. Biochem. J. 254 (1988) 915-918. [PMID: 3196304]

6. Battersby, A.R. Tetrapyrroles: the pigments of life. Nat. Prod. Rep. 17 (2000) 507-526. [PMID: 11152419]

[EC 2.5.1.61 created 1972 as EC 4.3.1.8, transferred 2003 to EC 2.6.1.61]

EC 2.5.1.62

Common name: chlorophyll synthase

Reaction: chlorophyllide a + phytyl diphosphate = chlorophyll a + diphosphate

For diagram of reaction click here (chlorophyll biosynthesis).

Systematic name: chlorophyllide-a:phytyl-diphosphate phytyltransferase

Comments: Requires Mg2+. The enzyme is modified by binding of the first substrate, phytyl diphosphate, before reaction of the modified enzyme with the second substrate, chlorophyllide a, can occur. The reaction also occurs when phytyl diphosphate is replaced by geranylgeranyl diphosphate.

References:

1. Schmid, H.C., Rassadina, V., Oster, U., Schoch, S. and Rüdiger, W. Pre-loading of chlorophyll synthase with tetraprenyl diphosphate is an obligatory step in chlorophyll biosynthesis. Biol. Chem. 383 (2002) 1769-1778. [PMID: 12530542]

2. Oster, U., Bauer, C.E. and Rüdiger, W. Characterization of chlorophyll a and bacteriochlorophyll a synthases by heterologous expression in Escherichia coli. J. Biol. Chem. 272 (1997) 9671-9676. [PMID: 9092496]

3. Rüdiger, W., Benz, J. and Guthoff. C. Detection and partial characterization of activity of chlorophyll synthetase in etioplast membranes. Eur. J. Biochem. 109 (1980) 193-200. [PMID: 7408876]

[EC 2.5.1.62 created 2003]

EC 2.5.1.63

Common name: adenosyl-fluoride synthase

Reaction: S-adenosyl-L-methionine + fluoride = 5'-deoxy-5'-fluoroadenosine + L-methionine

Other name(s): fluorinase

Systematic name: S-adenosyl-L-methionine:fluoride adenosyltransferase

References:

1. O'Hagan, D., Schaffrath, C., Cobb, S.L., Hamilton, J.T. and Murphy, C.D. Biosynthesis of an organofluorine molecule. Nature 416 (2002) 279 only. [PMID: 11907567]

[EC 2.5.1.63 created 2003]

*EC 2.6.1.55

Common name: taurine—2-oxoglutarate transaminase

Reaction: taurine + 2-oxoglutarate = sulfoacetaldehyde + L-glutamate

Other name(s): taurine aminotransferase; taurine transaminase; taurine—α-ketoglutarate aminotransferase; taurine—glutamate transaminase

Systematic name: taurine:2-oxoglutarate aminotransferase

Comments: A pyridoxal-phosphate protein. Also acts on D,L-3-amino-isobutanoate, β-alanine and 3-aminopropanesulfonate. Involved in the microbial utilization of β-alanine.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9076-52-2

References:

1. Toyama, S., Misono, H. and Soda, K. Crystalline taurine:α-ketoglutarate aminotransferase from Achromobacter superficialis. Biochem. Biophys. Res. Commun. 46 (1972) 1374-1379. [PMID: 5012173]

2. Cook, A.M. and Denger, K. Dissimilation of the C2 sulfonates. Arch. Microbiol. 179 (2002) 1-6. [PMID: 12471498]

[EC 2.6.1.55 created 1976, modified 2003]

EC 2.6.1.77

Common name: taurine—pyruvate aminotransferase

Reaction: taurine + pyruvate = L-alanine + 2-sulfoacetaldehyde

For diagram click here.

Other name(s): Tpa

Systematic name: taurine:pyruvate aminotransferase

Comments: The enzyme from Bilophila wadsworthia requires pryidoxal 5'-phosphate as a cofactor, is reversible, and catalyses the first step of anaerobic taurine degradation. Hypotaurine (i.e. 2-aminoethanesulfinate) and β-alanine are also significant donors of an amino group. Unlike, EC 2.6.1.55, taurine-2-oxoglutarate transaminase, 2-oxoglutarate is not an acceptor of amino groups.

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

References:

1. Laue, H. and Cook, A.M. Biochemical and molecular characterization of taurine:pyruvate transaminase from the anaerobe Bilophila wadsworthia. Eur. J. Biochem. 267 (2000) 6841-6848. [PMID: 11082195]

2. Cook, A.M. and Denger, K. Dissimilation of the C2 sulfonates. Arch. Microbiol. 179 (2002) 1-6. [PMID: 12471498]

3. Masepohl, B., Fuhrer, F. and Klipp, W. Genetic analysis of a Rhodobacter capsulatus gene region involved in utilization of taurine as a sulfur source. FEMS Microbiol. Lett. 205 (2001) 105-111. [PMID: 11728723]

[EC 2.6.1.77 created 2003]

EC 2.8.3.15

Common name: succinyl-CoA:(R)-benzylsuccinate CoA-transferase

Reaction: succinyl-CoA + (R)-2-benzylsuccinate = succinate + (R)-2-benzylsuccinyl-CoA

For diagram click here.

Other name(s): benzylsuccinate CoA-transferase

Systematic name: succinyl-CoA:(R)-2-benzylsuccinate CoA-transferase

Comments: Involved in anaerobic catabolism of toluene and is a strictly toluene-induced enzyme that catalyses the reversible regio- and enantio-selective synthesis of (R)-2-benzylsuccinyl-CoA. The enzyme from Thauera aromatica is inactive when (R)-benzylsuccinate is replaced by (S)-benzylsuccinate.

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

References:

1. Leutwein, C. and Heider, J. Succinyl-CoA:(R)-benzylsuccinate CoA-transferase: an enzyme of the anaerobic toluene catabolic pathway in denitrifying bacteria. J. Bacteriol. 183 (2001) 4288-4295. [PMID: 11418570]

2. Leutwein, C. and Heider, J. Anaerobic toluene-catabolic pathway in denitrifying Thauera aromatica: activation and β-oxidation of the first intermediate, (R)-(+)-benzylsuccinate. Microbiology 145 (1999) 3265-3271. [PMID: 10589736]

3. Leuthner, B. and Heider, J. Anaerobic toluene catabolism of Thauera aromatica: the bbs operon codes for enzymes of β oxidation of the intermediate benzylsuccinate. J. Bacteriol. 182 (2000) 272-277. [PMID: 10629170]

4. Heider, J. A new familiy of CoA-transferases. FEBS Lett. 509 (2001) 345-349. [PMID: 11749953]

[EC 2.8.3.15 created 2003]

EC 2.8.3.16

Common name: formyl-CoA transferase

Reaction: formyl-CoA + oxalate = formate + oxalyl-CoA

Other name(s): formyl-coenzyme A transferase; formyl-CoA oxalate CoA-transferase

Systematic name: formyl-CoA:oxalate CoA-transferase

Comments: The enzyme from Oxalobacter formigenes can also catalyse the transfer of CoA from formyl-CoA to succinate.

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

References:

1. Baetz, A.L. and Allison, M.J. Purification and characterization of formyl-coenzyme A transferase from Oxalobacter formigenes. J. Bacteriol. 172 (1990) 3537-3540. [PMID: 2361939]

2. Sidhu, H., Ogden, S.D., Lung, H.Y., Luttge, B.G., Baetz, A.L. and Peck, A.B. DNA sequencing and expression of the formyl coenzyme A transferase gene, frc, from Oxalobacter formigenes. J. Bacteriol. 179 (1997) 3378-3381. [PMID: 9150242]

[EC 2.8.3.16 created 2003]

EC 2.8.3.17

Common name: cinnamoyl-CoA:phenyllactate CoA-transferase

Reaction: (E)-cinnamoyl-CoA + (R)-phenyllactate = (E)-cinnamate + (R)-phenyllactyl-CoA

Other name(s): FldA

Systematic name: (E)-cinnamoyl-CoA:(R)-phenyllactate CoA-transferase

Comments: 3-Phenylproprionate is a better CoA acceptor than (R)-phenyllactate in vitro. The enzyme from Clostridium sporogenes is specific for derivatives of 3-phenylpropionate and 4-phenylbutyrate.

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

References:

1. Dickert, S., Pierik, A.J., Linder, D. and Buckel, W. The involvement of coenzyme A esters in the dehydration of (R)-phenyllactate to (E)-cinnamate by Clostridium sporogenes. Eur. J. Biochem. 267 (2000) 3874-3884. [PMID: 10849007]

[EC 2.8.3.17 created 2003]

EC 3.5.3.22

Common name: proclavaminate amidinohydrolase

Reaction: amidinoproclavaminate + H2O = proclavaminate + urea

For diagram click here.

Other name(s): PAH; proclavaminate amidino hydrolase

Systematic name: amidinoproclavaminate amidinohydrolase

Comments: Forms part of the pathway for the biosythesis of the β-lactamase inhibitor clavulanate in Streptomyces clavuligerus. It carries out an intermediary reaction between the first reaction of EC 1.14.11.21, clavaminate synthase, and the second and third reactions of that enzyme. Requires Mn2+.

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

References:

1. Salowe, S.P., Krol, W.J., Iwatareuyl, D. and Townsend, C.A. Elucidation of the order of oxidations and identification of an intermediate in the multistep clavaminate synthase reaction. Biochemistry 30 (1991) 2281-2292. [PMID: 1998687]

2. Zhou, J., Kelly, W.L., Bachmann, B.O., Gunsior, M., Townsend, C.A. and Solomon, E.I. Spectroscopic studies of substrate interactions with clavaminate synthase 2, a multifunctional α-KG-dependent non-heme iron enzyme: Correlation with mechanisms and reactivities. J. Am. Chem. Soc. 123 (2001) 7388-7389.

3. Townsend, C.A. New reactions in clavulanic acid biosynthesis. Curr. Opin. Chem. Biol. 6 (2002) 583-589. [PMID: 12413541]

4. Wu, T.K., Busby, R.W., Houston, T.A., McIlwaine, D.B., Egan, L.A. and Townsend, C.A. Identification, cloning, sequencing, and overexpression of the gene encoding proclavaminate amidino hydrolase and characterization of protein function in clavulanic acid biosynthesis. J. Bacteriol. 177 (1995) 3714-3720. [PMID: 7601835]

[EC 3.5.3.22 created 2003]

EC 3.5.4.29

Common name: GTP cyclohydrolase IIa

Reaction: GTP + 3 H2O = 2-amino-5-formylamino-6-hydroxy-4-(5-phosphoribosylamino)-pyrimidine + 2 phosphate

For diagram click here.

Systematic name: GTP 8,9-hydrolase (phosphate-forming)

Comments: Requires Mg2+. This enzyme catalyses the hydrolysis of the imidazole ring of guanosine 5'-triphosphate, N7-methylguanosine 5'-triphosphate or inosine 5'-triphosphate. Xanthosine 5'-triphosphate and ATP are not substrates. It also catalyses the hydrolysis of diphosphate to form two equivalents of phosphate. Unlike GTP cyclohydrolase II (EC 3.5.4.25), this enzyme does not release formate, but does hydrolyze the diphosphate from GTP to phosphate.

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

References:

1. Graham, D.E., Xu, H. and White, R.H. A member of a new class of GTP cyclohydrolases produces formylaminopyrimidine nucleotide monophosphates. Biochemistry 41 (2002) 15074-15084. [PMID: 12475257]

[EC 3.5.4.29 created 2003]

*EC 4.1.1.39

Common name: ribulose-bisphosphate carboxylase

Reaction: D-ribulose 1,5-bisphosphate + CO2 + H2O = 2 3-phospho-D-glycerate + 2 H+

For diagram click here.

Other name(s): D-ribulose 1,5-diphosphate carboxylase; D-ribulose-1,5-bisphosphate carboxylase; RuBP carboxylase; carboxydismutase; diphosphoribulose carboxylase; ribulose 1,5-bisphosphate carboxylase; ribulose 1,5-bisphosphate carboxylase/oxygenase; ribulose 1,5-diphosphate carboxylase; ribulose 1,5-diphosphate carboxylase/oxygenase; ribulose bisphosphate carboxylase/oxygenase; ribulose diphosphate carboxylase; ribulose diphosphate carboxylase/oxygenase; rubisco

Systematic name: 3-phospho-D-glycerate carboxy-lyase (dimerizing)

Comments: Will utilize O2 instead of CO2, forming 3-phospho-D-glycerate and 2-phosphoglycolate.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 9027-23-0

References:

1. Bowles, G., Ogren, W.L. and Hageman, R.H. Phosphoglycolate production catalyzed by ribulose diphosphate carboxylase. Biochem. Biophys. Res. Commun. 45 (1971) 716-722. [PMID: 4331471]

2. Wishnick, M., Lane, M.D., Scrutton, M.C. and Mildvan, A.S. The presence of tightly bound copper in ribulose diphosphate carboxylase from spinach. J. Biol. Chem. 244 (1969) 5761-5763. [PMID: 4310607]

[EC 4.1.1.39 created 1965, modified 2001, modified 2003]

*EC 4.1.1.70

Common name: glutaconyl-CoA decarboxylase

Reaction: 4-carboxybut-2-enoyl-CoA = but-2-enoyl-CoA + CO2

Glossary: glutaconyl-CoA = 4-carboxybut-2-enoyl-CoA

Other name(s): glutaconyl coenzyme A decarboxylase; pent-2-enoyl-CoA carboxy-lyase

Systematic name: 4-carboxybut-2-enoyl-CoA carboxy-lyase

Comments: The enzyme from Acidaminococcus fermentans is a biotinyl-protein, requires Na+, and acts as a sodium pump. Prior to the Na+-dependent decarboxylation, the carboxylate is transferred to biotin in a Na+-independent manner. The conserved lysine, to which biotin forms an amide bond, is located 34 amino acids before the C-terminus, flanked on both sides by two methionine residues, which are conserved in every biotin-dependent enzyme.

Links to other databases: BRENDA, EXPASY, KEGG, UM-BBD, WIT, CAS registry number: 84399-93-9

References:

1. Buckel, W.S. and Semmler, R. Purification, characterisation and reconstitution of glutaconyl-CoA decarboxylase, a biotin-dependent sodium pump from anaerobic bacteria. Eur. J. Biochem. 136 (1983) 427-434. [PMID: 6628393]

2. Buckel, W. Sodium ion-translocating decarboxylases. Biochim. Biophys. Acta 1505 (2001) 15-27. [PMID: 11248185]

[EC 4.1.1.70 created 1986, modified 2003]

EC 4.1.3.38

Common name: aminodeoxychorismate lyase

Reaction: 4-amino-4-deoxychorismate = 4-aminobenzoate + pyruvate

For diagram of reaction click here (folate biosynthesis).

Other name(s): enzyme X; 4-amino-4-deoxychorismate lyase

Systematic name: 4-amino-4-deoxychorismate pyruvate-lyase

Comments: A pyridoxal-phosphate protein. Forms part of the folate biosynthesis pathway. Acts on 4-amino-4-deoxychorismate, the product of EC 6.3.5.8, aminodeoxychorismate synthase, to form p-aminobenzoate.

References:

1. Ye, Q.Z., Liu, J. and Walsh, C.T. p-Aminobenzoate synthesis in Escherichia coli: purification and characterization of PabB as aminodeoxychorismate synthase and enzyme X as aminodeoxychorismate lyase. Proc. Natl. Acad. Sci. USA 87 (1990) 9391-9395. [PMID: 2251281]

2. Green, J.M., Merkel, W.K. and Nichols, B.P. Characterization and sequence of Escherichia coli pabC, the gene encoding aminodeoxychorismate lyase, a pyridoxal phosphate-containing enzyme. J. Bacteriol. 174 (1992) 5317-5323. [PMID: 1644759]

3. Nakai, T., Mizutani, H., Miyahara, I., Hirotsu, K., Takeda, S., Jhee, K.H., Yoshimura, T. and Esaki, N. Three-dimensional structure of 4-amino-4-deoxychorismate lyase from Escherichia coli. J. Biochem. 128 (2000) 29-38. [PMID: 10876155]

[EC 4.1.3.38 created 2003]

*EC 4.2.1.3

Common name: aconitate hydratase

Reaction: citrate = cis-aconitate + H2O

For diagram click here (see also glyoxylate cycle and citric acid cycle).

Other name(s): cis-aconitase; aconitase

Systematic name: citrate(isocitrate) hydro-lyase

Comments: Besides interconverting citrate and cis-aconitate, it also interconverts cis-aconitate with isocitrate and, hence, interconverts citrate and isocitrate. The equilibrium mixture is 91% citrate, 6% isocitrate and 3% aconitate. cis-Aconitate is used to designate the isomer (Z)-prop-1-ene-1,2,3-tricarboxylate. An iron-sulfur protein, containing a [4Fe-4S] cluster to which the substrate binds.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 9024-25-3

References:

1. Dickman, S.R. Aconitase. In: Boyer, P.D., Lardy, H. and Myrbäck, K (Eds.), The Enzymes, 2nd ed., vol. 5, Academic Press, New York, 1961, pp. 495-510.

2. Morrison, J.F. The purification of aconitase. Biochem. J. 56 (1954) 99-105.

3. Lauble, H., Kennedy, M.C., Beinert, H. and Stout, C.D. Crystal structures of aconitase with trans-aconitate and nitrocitrate bound. J. Mol. Biol. 237 (1994) 437-451. [PMID: 8151704]

[EC 4.2.1.3 created 1961, modified 2003]

EC 4.2.3.20

Common name: (R)-limonene synthase

Reaction: geranyl diphosphate = (+)-(R)-limonene + diphosphate

For diagram click here.

Other name(s): (+)-limonene synthase

Systematic name: geranyldiphosphate diphosphate lyase [(+)-(R)-limonene-forming]

Comments: Forms the first step of carvone biosynthesis in caraway. The enzyme from Carum carvi (caraway) seeds requires a divalent metal ion (preferably Mn2+) for catalysis.

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

References:

1. Bouwmeester, H.J., Gershenzon, J., Konings, M.C.J.M. and Croteau, R. Biosynthesis of the monoterpenes limonene and carvone in the fruit of caraway. I. Demonstration of enzyme activities and their changes with development. Plant Physiol. 117 (1998) 901-912. [PMID: 9662532]

2. Lucker, J., El Tamer, M.K., Schwab, W., Verstappen, F.W., van der Plas, L.H., Bouwmeester, H.J. and Verhoeven, H.A. Monoterpene biosynthesis in lemon (Citrus limon). cDNA isolation and functional analysis of four monoterpene synthases. Eur. J. Biochem. 269 (2000) 3160-3171. [PMID: 12084056]

3. Maruyama, T., Ito, M., Kiuchi, F. and Honda, G. Molecular cloning, functional expression and characterization of d-limonene synthase from Schizonepeta tenuifolia. Biol. Pharm. Bull. 24 (2001) 373-377. [PMID: 11305598]

[EC 4.2.3.20 created 2003]

[EC 4.3.1.8 Transferred entry: now EC 2.5.1.61 hydroxymethylbilane synthase. (EC 4.3.1.8 created 1972, deleted 2003)]

[EC 4.4.1.12 Deleted entry: sulfoacetaldehyde lyase. Activity due to EC 2.3.3.15, sulfoacetaldehyde acetyltransferase. (EC 4.4.1.12 created 1976, deleted 2003)]

EC 4.4.1.19

Common name: phosphosulfolactate synthase

Reaction: (2R)-O-phospho-3-sulfolactate = sulfite + phosphoenolpyruvate

For diagram click here.

Other name(s): (2R)-phospho-3-sulfolactate synthase

Systematic name: (2R)-O-phospho-3-sulfolactate sulfo-lyase

Comments: Requires Mg2+. The enzyme from Methanococcus jannaschii catalyses the Michael addition of sulfite to phosphoenolpyruvate. It specifically requires phosphoenolpyruvate and its broad alkaline pH optimum suggests that it uses sulfite rather than bisulfite.

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

References:

1. Graham, D.E., Xu, H. and White, R.H. Identification of coenzyme M biosynthetic phosphosulfolactate synthase: a new family of sulfonate-biosynthesizing enzymes. J. Biol. Chem. 277 (2002) 13421-13429. [PMID: 11830598]

[EC 4.4.1.19 created 2003]

*EC 5.4.3.4

Common name: D-lysine 5,6-aminomutase

Reaction: D-lysine = 2,5-diaminohexanoate

Other name(s): D-α-lysine mutase; adenosylcobalamin-dependent D-lysine 5, 6-aminomutase

Systematic name: D-2,6-diaminohexanoate 5,6-aminomutase

Comments: Requires a cobamide coenzyme.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 9075-70-1

References:

1. Morley, C.G.D. and Stadtman, T.C. Studies on the fermentation of D-α-lysine. Purification and properties of an adenosine triphosphate regulated B12-coenzyme-dependent D-α-lysine mutase complex from Clostridium sticklandii. Biochemistry 9 (1970) 4890-4900. [PMID: 5480154]

2. Stadtman, T.C. and Tasi, L. A cobamide coenzyme dependent migration of the ε-amino group of D-lysine. Biochem. Biophys. Res. Commun. 28 (1967) 920-926. [PMID: 4229021]

[EC 5.4.3.4 created 1972, modified 2003]

*EC 5.4.3.5

Common name: D-ornithine 4,5-aminomutase

Reaction: D-ornithine = (2R,4S)-2,4-diaminopentanoate

Other name(s): D-α-ornithine 5,4-aminomutase; D-ornithine aminomutase

Systematic name: D-ornithine 4,5-aminomutase

Comments: A pyridoxal-phosphate protein that requires a cobamide coenzyme for activity.

Links to other databases: BRENDA, EXPASY, GTD, KEGG, WIT, CAS registry number: 62213-30-3

References:

1. Somack, R. and Costilow, R.N. Purification and properties of a pyridoxal phosphate and coenzyme B12 dependent D-α-ornithine 5,4-aminomutase. Biochemistry 12 (1973) 2597-2604. [PMID: 4711468]

[EC 5.4.3.5 created 1972 as EC 5.4.3.1, transferred 1976 to EC 5.4.3.5, modified 2003]

EC 5.4.4 Transferring Hydroxy Groups

EC 5.4.4.1

Common name: (hydroxyamino)benzene mutase

Reaction: (hydroxyamino)benzene = 2-aminophenol

Other name(s): HAB mutase; hydroxylaminobenzene hydroxymutase; hydroxylaminobenzene mutase

Systematic name: (hydroxyamino)benzene hydroxymutase

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

References:

1. He, Z., Nadeau, L.J. and Spain, J.C. Characterization of hydroxylaminobenzene mutase from pNBZ139 cloned from Pseudomonas pseudoalcaligenes JS45: a highly-associated sodium-dodecyl-sulfate-stable enzyme catalyzing an intramolecular transfer of hydroxyl group. Eur. J. Biochem. 267 (2000) 1110-1116. [PMID: 10672020]

2. Davis, J.K., Paoli, G.C., He, Z., Nadeau, L.J., Somerville, C.C. and Spain, J.C. Sequence analysis and initial characterization of two isozymes of hydroxylaminobenzene mutase from Pseudomonas pseudoalcaligenes JS45. Appl. Environ. Microbiol. 66 (2000) 2965-2971. [PMID: 10877793]

[EC 5.4.4.1 created 2003]

EC 5.4.4.2

Common name: isochorismate synthase

Reaction: chorismate = isochorismate

For diagram click here.

Systematic name: isochorismate hydroxymutase

Comments: Requires Mg2+. The reaction is reversible.

Links to other databases: BRENDA, EXPASY, KEGG, WIT, CAS registry number: 37318-53-9

References:

1. Young, I.G. and Gibson, F. Regulation of the enzymes involved in the biosynthesis of 2,3-dihydroxybenzoic acid in Aerobacter aerogenes and Escherichia coli. Biochim. Biophys. Acta 177 (1969) 401-411. [PMID: 4306838]

2. van Tegelen, L.J., Moreno, P.R., Croes, A.F., Verpoorte, R. and Wullems, G.J. Purification and cDNA cloning of isochorismate synthase from elicited cell cultures of Catharanthus roseus. Plant Physiol. 119 (1999) 705-712. [PMID: 9952467]

3. Dahm, C., Müller, R., Schulte, G., Schmidt, K. and Leistner, E. The role of isochorismate hydroxymutase genes entC and menF in enterobactin and menaquinone biosynthesis in Escherichia coli. Biochim. Biophys. Acta 1425 (1998) 377-386. [PMID: 9795253]

[EC 5.4.4.2 created 1972 as EC 5.4.99.6, transferred 2003 to EC 5.4.4.2]

[EC 5.4.99.6 Transferred entry: now EC 5.4.4.2 isochorismate synthase. (EC 5.4.99.6 created 1972, deleted 2003)]

EC 6.3.3.4

Common name: (carboxyethyl)arginine β-lactam-synthase

Reaction: ATP + L-N2-(2-carboxyethyl)arginine = AMP + diphosphate + deoxyamidinoproclavaminate

For diagram click here.

Systematic name: L-N2-(2-carboxyethyl)arginine cyclo-ligase (AMP-forming)

Comments: Forms part of the pathway for the biosythesis of the β-lactamase inhibitor clavulanate in Streptomyces clavuligerus. It has been proposed [3] that L-N2-(2-carboxyethyl)arginine is first converted into an acyl-AMP by reaction with ATP and loss of diphosphate, and that the β-lactam ring is then formed by the intramolecular attack of the β-nitrogen on the activated carboxy group.

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

References:

1. Zhou, J., Kelly, W.L., Bachmann, B.O., Gunsior, M., Townsend, C.A. and Solomon, E.I. Spectroscopic studies of substrate interactions with clavaminate synthase 2, a multifunctional α-KG-dependent non-heme iron enzyme: Correlation with mechanisms and reactivities. J. Am. Chem. Soc. 123 (2001) 7388-7398.

2. Townsend, C.A. New reactions in clavulanic acid biosynthesis. Curr. Opin. Chem. Biol. 6 (2002) 583-589. [PMID: 12413541]

3. Bachmann, B.O., Li, R. and Townsend, C.A. β-Lactam synthetase: a new biosynthetic enzyme. Proc. Natl. Acad. Sci. USA 95 (1998) 9082-9086. [PMID: 9689037]

[EC 6.3.3.4 created 2003]

EC 6.3.5.8

Common name: aminodeoxychorismate synthase

Reaction: chorismate + L-glutamine = 4-amino-4-deoxychorismate + L-glutamate

For diagram of reaction click here (folate biosynthesis).

Other name(s): ADC synthase; 4-amino-4-deoxychorismate synthase; PabB

Systematic name: chorismate:L-glutamine amido-ligase

Comments: The enzyme is composed of two parts, PabA and PabB. In the absence of PabA and glutamine, PabB converts ammonia and chorismate into 4-amino-4-deoxychorismate (in the presence of Mg2+). PabA converts glutamine into glutamate only in the presence of stoichiometric amounts of PabB. This enzyme is coupled with EC 4.1.3.38, aminodeoxychorismate lyase, to form p-aminobenzoate.

References:

1. Ye, Q.Z., Liu, J. and Walsh, C.T. p-Aminobenzoate synthesis in Escherichia coli: purification and characterization of PabB as aminodeoxychorismate synthase and enzyme X as aminodeoxychorismate lyase. Proc. Natl. Acad. Sci. USA 87 (1990) 9391-9395. [PMID: 2251281]

2. Viswanathan, V.K., Green, J.M. and Nichols, B.P. Kinetic characterization of 4-amino 4-deoxychorismate synthase from Escherichia coli. J. Bacteriol. 177 (1995) 5918-5923. [PMID: 7592344]

[EC 6.3.5.8 created 2003]

EC 6.6 Forming nitrogen—metal bonds

EC 6.6.1 Forming coordination complexes

EC 6.6.1.1

Common name: magnesium chelatase

Reaction: ATP + protoporphyrin IX + Mg2+ + H2O = ADP + phosphate + Mg-protoporphyrin IX + 2 H+

For diagram of reaction click here (heme and chlorophyll biosynthesis).

Other name(s): protoporphyrin IX magnesium-chelatase; protoporphyrin IX Mg-chelatase; magnesium-protoporphyrin IX chelatase; magnesium-protoporphyrin chelatase; magnesium-chelatase; Mg-chelatase; Mg-protoporphyrin IX magnesio-lyase

Systematic name: Mg-protoporphyrin IX magnesium-lyase

Comments: This is the first committed step of chlorophyll biosynthesis and is a branchpoint of two major routes in the tetrapyrrole pathway.

References:

1. Walker, C.J. and Weinstein, J.D. In vitro assay of the chlorophyll biosynthetic enzyme Mg-chelatase: resolution of the activity into soluble and membrane-bound fractions. Proc. Natl. Acad. Sci. USA 88 (1991) 5789-5793. [PMID: 11607197]

2. Walker, C.J. and Willows, R.D. Mechanism and regulation of Mg-chelatase. Biochem. J. 327 (1997) 321-333. [PMID: 9359397]

3. Fodje, M.N., Hansson, A., Hansson, M., Olsen, J.G., Gough, S., Willows, R.D. and Al-Karadaghi, S. Interplay between an AAA module and an integrin I domain may regulate the function of magnesium chelatase. J. Mol. Biol. 311 (2001) 111-122. [PMID: 11469861]

[EC 6.6.1.1 created 2003]


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