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An asterisk before 'EC' indicates that this is an amendment to an existing enzyme rather than a new enzyme entry.
Accepted name: sn-glycerol-1-phosphate dehydrogenase
Reaction: sn-glycerol-1-phosphate + NAD(P)+ = glycerone phosphate + NAD(P)H + H+
For diagram of reaction, click here
Glossary: glycerone phosphate = dihydroxyacetone phosphate = 3-hydroxy-2-oxopropyl phosphate
Other name(s): glycerol-1-phosphate dehydrogenase [NAD(P)+]; sn-glycerol-1-phosphate:NAD+ oxidoreductase; G-1-P dehydrogenase; Gro1PDH
Systematic name: sn-glycerol-1-phosphate:NAD(P)+ 2-oxidoreductase
Comments: This Zn2+-dependent metalloenzyme is responsible for the formation of Archaea-specific sn-glycerol-1-phosphate, the first step in the biosynthesis of polar lipids in Archaea. It is the enantiomer of sn-glycerol 3-phosphate, the form of glycerophosphate found in bacteria and eukaryotes. The other enzymes involved in the biosynthesis of polar lipids in Archaea are EC 2.5.1.41 (phosphoglycerol geranylgeranyltransferase) and EC 2.5.1.42 (geranylgeranylglycerol-phosphate geranylgeranyltransferase), which together alkylate the hydroxy groups of glycerol 1-phosphate to give unsaturated archaetidic acid, which is acted upon by EC 2.7.7.67 (CDP-archaeol synthase) to form CDP-unsaturated archaeol. The final step in the pathway involves the addition of L-serine, with concomitant removal of CMP, leading to the production of unsaturated archaetidylserine [4]. Activity of the enzyme is stimulated by K+ [2].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number: 204594-18-3
References:
1. Nishihara, M. and Koga, Y. sn-Glycerol-1-phosphate dehydrogenase in Methanobacterium thermoautotrophicum: key enzyme in biosynthesis of the enantiomeric glycerophosphate backbone of ether phospholipids of archaebacteria. J. Biochem. 117 (1995) 933-935. [PMID: 8586635]
2. Nishihara, M. and Koga, Y. Purification and properties of sn-glycerol-1-phosphate dehydrogenase from Methanobacterium thermoautotrophicum: characterization of the biosynthetic enzyme for the enantiomeric glycerophosphate backbone of ether polar lipids of Archaea. J. Biochem. 122 (1997) 572-576. [PMID: 9348086]
3. Koga, Y., Kyuragi, T., Nishihara, M. and Sone, N. Did archaeal and bacterial cells arise independently from noncellular precursors? A hypothesis stating that the advent of membrane phospholipid with enantiomeric glycerophosphate backbones caused the separation of the two lines of descent. J. Mol. Evol. 46 (1998) 54-63. [PMID: 9419225]
4. Morii, H., Nishihara, M. and Koga, Y. CTP:2,3-di-O-geranylgeranyl-sn-glycero-1-phosphate cytidyltransferase in the methanogenic archaeon Methanothermobacter thermoautotrophicus. J. Biol. Chem. 275 (2000) 36568-36574. [PMID: 10960477]
5. Han, J.S. and Ishikawa, K. Active site of Zn2+-dependent sn-glycerol-1-phosphate dehydrogenase from Aeropyrum pernix K1. Archaea 1 (2005) 311-317. [PMID: 15876564]
Accepted name: glycerol-3-phosphate dehydrogenase
Reaction: sn-glycerol 3-phosphate + a quinone = glycerone phosphate + a quinol
Glossary: glycerone phosphate = dihydroxyacetone phosphate = 3-hydroxy-2-oxopropyl phosphate
Other name(s): α-glycerophosphate dehydrogenase; α-glycerophosphate dehydrogenase (acceptor); anaerobic glycerol-3-phosphate dehydrogenase; DL-glycerol 3-phosphate oxidase (misleading); FAD-dependent glycerol-3-phosphate dehydrogenase; FAD-dependent sn-glycerol-3-phosphate dehydrogenase; FAD-GPDH; FAD-linked glycerol 3-phosphate dehydrogenase; FAD-linked L-glycerol-3-phosphate dehydrogenase; flavin-linked glycerol-3-phosphate dehydrogenase; flavoprotein-linked L-glycerol 3-phosphate dehydrogenase; glycerol 3-phosphate cytochrome c reductase (misleading); glycerol phosphate dehydrogenase; glycerol phosphate dehydrogenase (acceptor); glycerol phosphate dehydrogenase (FAD); glycerol-3-phosphate CoQ reductase; glycerol-3-phosphate dehydrogenase (flavin-linked); glycerol-3-phosphate:CoQ reductase; glycerophosphate dehydrogenase; L-3-glycerophosphate-ubiquinone oxidoreductase; L-glycerol-3-phosphate dehydrogenase (ambiguous); L-glycerophosphate dehydrogenase; mGPD; mitochondrial glycerol phosphate dehydrogenase; NAD+-independent glycerol phosphate dehydrogenase; pyridine nucleotide-independent L-glycerol 3-phosphate dehydrogenase; sn-glycerol 3-phosphate oxidase (misleading); sn-glycerol-3-phosphate dehydrogenase; sn-glycerol-3-phosphate:(acceptor) 2-oxidoreductase; sn-glycerol-3-phosphate:acceptor 2-oxidoreductase
Systematic name: sn-glycerol 3-phosphate:quinone oxidoreductase
Comments: This flavin-dependent dehydrogenase is an essential membrane enzyme, functioning at the central junction of glycolysis, respiration and phospholipid biosynthesis. In bacteria, the enzyme is localized to the cytoplasmic membrane [6], while in eukaryotes it is tightly bound to the outer surface of the inner mitochondrial membrane [2]. In eukaryotes, this enzyme, together with the cytosolic enzyme EC 1.1.1.8, glycerol-3-phosphate dehydrogenase (NAD+), forms the glycerol-3-phosphate shuttle by which NADH produced in the cytosol, primarily from glycolysis, can be reoxidized to NAD+ by the mitochondrial electron-transport chain [3]. This shuttle plays a critical role in transferring reducing equivalents from cytosolic NADH into the mitochondrial matrix [7,8]. Insect flight muscle uses only CoQ10 as the physiological quinone whereas hamster and rat mitochondria use mainly CoQ9 [4]. The enzyme is activated by calcium [3].
References:
1. Ringler, R.L. Studies on the mitochondrial α-glycerophosphate dehydrogenase. II. Extraction and partial purification of the dehydrogenase from pig brain. J. Biol. Chem. 236 (1961) 1192-1198. [PMID: 13741763]
2. Schryvers, A., Lohmeier, E. and Weiner, J.H. Chemical and functional properties of the native and reconstituted forms of the membrane-bound, aerobic glycerol-3-phosphate dehydrogenase of Escherichia coli. J. Biol. Chem. 253 (1978) 783-788. [PMID: 340460]
3. MacDonald, M.J. and Brown, L.J. Calcium activation of mitochondrial glycerol phosphate dehydrogenase restudied. Arch. Biochem. Biophys. 326 (1996) 79-84. [PMID: 8579375]
4. Rauchová, H., Fato, R., Drahota, Z. and Lenaz, G. Steady-state kinetics of reduction of coenzyme Q analogs by glycerol-3-phosphate dehydrogenase in brown adipose tissue mitochondria. Arch. Biochem. Biophys. 344 (1997) 235-241. [PMID: 9244403]
5. Shen, W., Wei, Y., Dauk, M., Zheng, Z. and Zou, J. Identification of a mitochondrial glycerol-3-phosphate dehydrogenase from Arabidopsis thaliana: evidence for a mitochondrial glycerol-3-phosphate shuttle in plants. FEBS Lett. 536 (2003) 92-96. [PMID: 12586344]
6. Walz, A.C., Demel, R.A., de Kruijff, B. and Mutzel, R. Aerobic sn-glycerol-3-phosphate dehydrogenase from Escherichia coli binds to the cytoplasmic membrane through an amphipathic α-helix. Biochem. J. 365 (2002) 471-479. [PMID: 11955283]
7. Ansell, R., Granath, K., Hohmann, S., Thevelein, J.M. and Adler, L. The two isoenzymes for yeast NAD+-dependent glycerol 3-phosphate dehydrogenase encoded by GPD1 and GPD2 have distinct roles in osmoadaptation and redox regulation. EMBO J. 16 (1997) 2179-2187. [PMID: 9171333]
8. Larsson, C., Påhlman, I.L., Ansell, R., Rigoulet, M., Adler, L. and Gustafsson, L. The importance of the glycerol 3-phosphate shuttle during aerobic growth of Saccharomyces cerevisiae. Yeast 14 (1998) 347-357. [PMID: 9559543]
[EC 1.1.99.5 Transferred entry: glycerol-3-phosphate dehydrogenase. As the acceptor is now known, the enzyme has been transferred to EC 1.1.5.3, glycerol-3-phosphate dehydrogenase. (EC 1.1.99.5 created 1961 as EC 1.1.2.1, transferred 1965 to EC 1.1.99.5, deleted 2009)]
Accepted name: abietadienal dehydrogenase
Reaction: abietadienal + H2O + NAD+ = abietate + NADH + 2 H+
For diagram click here.
Systematic name: abietadienal:NAD+ oxidoreductase
Comments: Abietic acid is the principle component of conifer resin. This enzyme catalyzes the last step of the pathway of abietic acid biosynthesis in Abies grandis (grand fir). The activity has been demonstrated in cell-free stem extracts of A. grandis, was present in the cytoplasm, and required NAD+ as cofactor [1]. The enzyme is expressed constitutively at a high level, and is not inducible by wounding of the plant tissue [2].
References:
1. Funk, C. and Croteau, R. Diterpenoid resin acid biosynthesis in conifers: characterization of two cytochrome P450-dependent monooxygenases and an aldehyde dehydrogenase involved in abietic acid biosynthesis. Arch. Biochem. Biophys. 308 (1994) 258-266. [PMID: 8311462]
2. Funk, C., Lewinsohn, E., Vogel, B.S., Steele, C.L. and Croteau, R. Regulation of oleoresinosis in grand fir (Abies grandis) (Coordinate induction of monoterpene and diterpene cyclases and two cytochrome P450-dependent diterpenoid hydroxylases by stem wounding). Plant Physiol. 106 (1994) 999-1005.[PMID: 12232380]
Accepted name: geranylgeranyl diphosphate reductase
Reaction: phytyl diphosphate + 3 NADP+ = geranylgeranyl diphosphate + 3 NADPH + 3 H+
For diagram click here.
Other name(s): geranylgeranyl reductase; CHL P
Systematic name: geranylgeranyl-diphosphate:NADP+ oxidoreductase
Comments: This enzyme also acts on geranylgeranyl-chlorophyll a. The reaction occurs in three steps. Which order the three double bonds are reduced is not known.
References:
1. Soll, J., Schultz, G., Rüdiger, W. and Benz, J. Hydrogenation of geranylgeraniol: two pathways exist in spinach chloroplasts. Plant Physiol. 71 (1983) 849-854. [PMID: 16662918]
2. Tanaka, R., Oster, U., Kruse, E., Rüdiger, W. and Grimm, B. Reduced activity of geranylgeranyl reductase leads to loss of chlorophyll and tocopherol and to partially geranylgeranylated chlorophyll in transgenic tobacco plants expressing antisense RNA for geranylgeranyl reductase Plant Physiol. 120 (1999) 695-704. [PMID: 10398704]
3. Keller, Y., Bouvier, F., d'Harlingue, A. and Camara, B. Metabolic compartmentation of plastid prenyllipid biosynthesis - evidence for the involvement of a multifunctional geranylgeranyl reductase. Eur. J. Biochem. 251 (1998) 413-417. [PMID: 9492312]
Accepted name: dihydroorotate dehydrogenase
Reaction: (S)-dihydroorotate + a quinone = orotate + a quinol
Other name(s): dihydroorotate:ubiquinone oxidoreductase; (S)-dihydroorotate:(acceptor) oxidoreductase; (S)-dihydroorotate:acceptor oxidoreductase; DHODH; DHOD; DHOdehase
Systematic name: (S)-dihydroorotate:quinone oxidoreductase
Comments: This Class 2 dihydroorotate dehydrogenase enzyme contains flavin [4]. The reaction, which takes place in the mitochondrial membrane, is the only redox reaction in the de-novo biosynthesis of pyrimidine nucleotides [2,4]. The best quinone electron acceptors for the enzyme from bovine liver are coenzymes Q6 and Q7, although simple quinones, such as benzoquinone, can also act as acceptor but at lower rates [2]. Methyl-, ethyl-, t-butyl and benzyl-(S)-dihydroorotates are also substrates, but 1- and 3-methyl and 1,3-dimethyl methyl-(S)-dihydroorotates are not [2].
References:
1. Forman, H.J. and Kennedy, J. Mammalian dihydroorotate dehydrogenase: physical and catalytic properties of the primary enzyme. Arch. Biochem. Biophys. 191 (1978) 23-31. [PMID: 216313]
2. Hines, V., Keys, L.D., III and Johnston, M. Purification and properties of the bovine liver mitochondrial dihydroorotate dehydrogenase. J. Biol. Chem. 261 (1986) 11386-11392. [PMID: 3733756]
3. Bader, B., Knecht, W., Fries, M. and Löffler, M. Expression, purification, and characterization of histidine-tagged rat and human flavoenzyme dihydroorotate dehydrogenase. Protein Expr. Purif. 13 (1998) 414-422. [PMID: 9693067]
4. Fagan, R.L., Nelson, M.N., Pagano, P.M. and Palfey, B.A. Mechanism of flavin reduction in Class 2 dihydroorotate dehydrogenases. Biochemistry 45 (2006) 14926-14932. [PMID: 17154530]
[EC 1.3.99.11 Transferred entry: dihydroorotate dehydrogenase. As the acceptor is now known, the enzyme has been transferred to EC 1.3.5.2, dihydroorotate dehydrogenase (EC 1.3.99.11 created 1983, deleted 2009)]
Accepted name: limonene 1,2-monooxygenase
Reaction: (1) (S)-limonene + NAD(P)H + H+ + O2 = 1,2-epoxymenth-8-ene + NAD(P)+ + H2O
(2) (R)-limonene + NAD(P)H + H+ + O2 = 1,2-epoxymenth-8-ene + NAD(P)+ + H2O
For diagram of reaction, click here
Glossary: limonene = a monoterpenoid
(S)-limonene = (–)-limonene
(R)-limonene = (+)-limonene
limonene-1,2-epoxide = 1,2-epoxymenth-8-ene = 1-methyl-4-(prop-1-en-2-yl)-7-oxabicyclo[4.1.0]heptane
Systematic name: limonene,NAD(P)H:oxygen oxidoreductase
Comments: A flavoprotein (FAD). Limonene is the most widespread terpene and is formed by more than 300 plants. Rhodococcus erythropolis DCL14, a Gram-positive bacterium, is able to grow on both (S)-limonene and (R)-limonene as the sole source of carbon and energy. NADPH can act instead of NADH, although more slowly. It has not been established if the product formed is optically pure or a mixture of two enantiomers.
References:
1. van der Werf, M.J., Swarts, H.J. and de Bont, J.A. Rhodococcus erythropolis DCL14 contains a novel degradation pathway for limonene. Appl. Environ. Microbiol. 65 (1999) 2092-2102. [PMID: 10224006]
Accepted name: abietadiene hydroxylase
Reaction: abietadiene + NADPH + H+ + O2 = abietadienol + NADP+ + H2O
For diagram click here.
Systematic name: abietadiene,NADPH:oxygen oxidoreductase (18-hydroxylating)
Comments: A heme-thiolate protein (P-450). This enzyme catalyzes a step in the pathway of abietic acid biosynthesis. The activity has been demonstrated in cell-free stem extracts of Abies grandis (grand fir) and Pinus contorta (lodgepole pine). The enzyme is localized in the microsomal fraction and requires both oxygen and NADPH. Inhibition by carbon monoxide and several substituted N-heterocyclic inhibitors suggests that the enzyme is a cytochrome P-450-dependent monooxygenase [1]. Activity is induced by wounding of the plant tissue [2].
References:
1. Funk, C. and Croteau, R. Diterpenoid resin acid biosynthesis in conifers: characterization of two cytochrome P450-dependent monooxygenases and an aldehyde dehydrogenase involved in abietic acid biosynthesis. Arch. Biochem. Biophys. 308 (1994) 258-266. [PMID: 8311462]
2. Funk, C., Lewinsohn, E., Vogel, B.S., Steele, C.L. and Croteau, R. Regulation of oleoresinosis in grand fir (Abies grandis) (Coordinate induction of monoterpene and diterpene cyclases and two cytochrome P450-dependent diterpenoid hydroxylases by stem wounding). Plant Physiol. 106 (1994) 999-1005.[PMID: 12232380]
Accepted name: abietadienol hydroxylase
Reaction: abietadienol + NADPH + H+ + O2 = abietadienal + NADP+ + 2 H2O
For diagram click here.
Other name(s): CYP720B1; PtAO
Systematic name: abietadienol,NADPH:oxygen oxidoreductase (18-hydroxylating)
Comments: A heme-thiolate protein (P-450). This enzyme catalyzes a step in the pathway of abietic acid biosynthesis. The activity has been demonstrated in cell-free stem extracts of Abies grandis (grand fir) and Pinus contorta (lodgepole pine) [1], and the gene encoding the enzyme has been identified in Pinus taeda (loblolly pine) [3]. The recombinant enzyme catalyzed the oxidation of multiple diterpene alcohol and aldehydes, including levopimaradienol, isopimara-7,15-dienol, isopimara-7,15-dienal, dehydroabietadienol, and dehydroabietadienal. It is not able to oxidize abietadiene.
References:
1. Funk, C. and Croteau, R. Diterpenoid resin acid biosynthesis in conifers: characterization of two cytochrome P450-dependent monooxygenases and an aldehyde dehydrogenase involved in abietic acid biosynthesis. Arch. Biochem. Biophys. 308 (1994) 258-266. [PMID: 8311462]
2. Funk, C., Lewinsohn, E., Vogel, B.S., Steele, C.L. and Croteau, R. Regulation of oleoresinosis in grand fir (Abies grandis) (Coordinate induction of monoterpene and diterpene cyclases and two cytochrome P450-dependent diterpenoid hydroxylases by stem wounding). Plant Physiol. 106 (1994) 999-1005.[PMID: 12232380]
3. Ro, D.K., Arimura, G., Lau, S.Y., Piers, E. and Bohlmann, J. Loblolly pine abietadienol/abietadienal oxidase PtAO (CYP720B1) is a multifunctional, multisubstrate cytochrome P450 monooxygenase. Proc. Natl. Acad. Sci. USA 102 (2005) 8060-8065. [PMID: 15911762]
Accepted name: geranylgeraniol 18-hydroxylase
Reaction: geranylgeraniol + NADPH + H+ + O2 = 18-hydroxygeranylgeraniol + NADP+ + H2O
For diagram click here.
glossary: plaunotol = 18-hydroxygeranylgeraniol
Other name(s): GGOH-18-hydroxylase
Systematic name: geranylgeraniol,NADPH:oxygen oxidoreductase (18-hydroxylating)
Comments: A heme-thiolate protein (P-450).
References:
1. Tansakul, P. and De-Eknamkul, W. Geranylgeraniol-18-hydroxylase: the last enzyme in the plaunotol biosynthetic pathway in Croton sublyratus. Phytochemistry 47 (1998) 1241-1246.
Accepted name: methanesulfonate monooxygenase
Reaction: methanesulfonate + FMNH2 + O2 = formaldehyde + FMN + sulfite + H2O
Glossary: methanesulfonate = CH3-SO3-
formaldehyde = H-CHO
Other name(s): mesylate monooxygenase; mesylate,reduced-FMN:oxygen oxidoreductase; MsmABC; methanesulfonic acid monooxygenase; MSA monooxygenase; MSAMO
Systematic name: methanesulfonate,FMNH2:oxygen oxidoreductase
Comments: Methanesulfonate is the simplest of the sulfonates and is a substrate for the growth of certain methylotrophic microorganisms. Compared with EC 1.14.14.5, alkanesulfonate monooxygenase, this enzyme has a restricted substrate range that includes only the short-chain aliphatic sulfonates (methane- to butanesulfonate) and excludes all larger molecules, such as arylsulfonates and aromatic sulfonates [1]. The enzyme from the bacterium Methylosulfonomonas methylovora is a multicomponent system comprising an hydroxylase, a reductase (MsmD; EC 1.5.1.29, FMN reductase) and a ferredoxin (MsmC). The hydroxylase has both large (MsmA) and small (MsmB) subunits, with each large subunit containing a Rieske-type [2Fe-2S] centre.
References:
1. de Marco, P., Moradas-Ferreira, P., Higgins, T.P., McDonald, I., Kenna, E.M. and Murrell, J.C. Molecular analysis of a novel methanesulfonic acid monooxygenase from the methylotroph Methylosulfonomonas methylovora. J. Bacteriol. 181 (1999) 2244-2251. [PMID: 10094704]
2. Higgins, T.P., Davey, M., Trickett, J., Kelly, D.P. and Murrell, J.C. Metabolism of methanesulfonic acid involves a multicomponent monooxygenase enzyme. Microbiology 142 (1996) 251-260. [PMID: 8932698]
Accepted name: 4-hydroxy-3-methylbut-2-enyl diphosphate reductase
Reaction: (1) isopentenyl diphosphate + NAD(P)+ + H2O = (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate + NAD(P)H + H+
(2) dimethylallyl diphosphate + NAD(P)+ + H2O = (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate + NAD(P)H + H+
For diagram of reaction, click here
Other name(s): isopentenyl-diphosphate:NADP+ oxidoreductase; LytB; (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate reductase; HMBPP reductase; IspH; LytB/IspH
Systematic name: isopentenyl-diphosphate:NAD(P)+ oxidoreductase
Comments: An iron-sulfur protein that contains either a [3Fe-4S](+) [6] or a [4Fe-4S] [5] cluster. This enzyme comprises a system in which ferredoxin is first reduced and subsequently reoxidized by an NAD(P)+-dependent reductase. This is the last enzyme in the non-mevalonate pathway for isoprenoid biosynthesis. This pathway, also known as the 1-deoxy-D-xylulose 5-phosphate (DOXP) or as the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway, is found in most bacteria and in plant chloroplasts. The enzyme acts in the reverse direction, producing a 5:1 mixture of isopentenyl diphosphate and dimethyallyl diphosphate.
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, PDB, CAS registry number: 512789-14-9
References:
1. Rohdich, F., Hecht, S., Gärtner, K., Adam, P., Krieger, C., Amslinger, S., Arigoni, D., Bacher, A. and Eisenreich, W. Studies on the nonmevalonate terpene biosynthetic pathway: Metabolic role of IspH (LytB) protein. Proc. Natl. Acad. Sci. USA 99 (2002) 1158-1163. [PMID: 11818558]
2. Hintz, M., Reichenberg, A., Altincicek, B., Bahr, U., Gschwind, R.M., Kollas, A.-K., Beck, E., Wiesner, J., Eberl, M. and Jomaa, H. Identification of (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate as a major activator for human T cells in Escherichia coli. FEBS Lett. 509 (2001) 317-322. [PMID: 11741609]
3. Charon, L., Pale-Grosdemange, C. and Rohmer, M. On the reduction steps in the mevalonate independent 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for isoprenoid biosynthesis in the bacterium Zymomonas mobilis. Tetrahedron Lett. 40 (1999) 7231-7234.
4. Röhrich, R.C., Englert, N., Troschke, K., Reichenberg, A., Hintz, M., Seeber, F., Balconi, E., Aliverti, A., Zanetti, G., Köhler, U., Pfeiffer, M., Beck, E., Jomaa, H. and Wiesner, J. Reconstitution of an apicoplast-localised electron transfer pathway involved in the isoprenoid biosynthesis of Plasmodium falciparum. FEBS Lett. 579 (2005) 6433-6438. [PMID: 16289098]
5. Wolff, M., Seemann, M., Bui, T.S.B., Frapart, Y., Tritsch, D., Garcia Estrabot, A., Rodríguez-Concepción, M., Boronat, A., Marquet, A. and Rohmer, M. Isoprenoid biosynthesis via the methylerythritol phosphate pathway: the (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase (LytB/IspH) from Escherichia coli is a [4Fe-4S] protein. FEBS Lett. 541 (2003) 115-120. [PMID: 12706830]
6. Gräwert, T., Kaiser, J., Zepeck, F., Laupitz, R., Hecht, S., Amslinger, S., Schramek, N., Schleicher, E., Weber, S., Haslbeck, M., Buchner, J., Rieder, C., Arigoni, D., Bacher, A., Eisenreich, W. and Rohdich, F. IspH protein of Escherichia coli: studies on iron-sulfur cluster implementation and catalysis. J. Am. Chem. Soc. 126 (2004) 12847-12855. [PMID: 15469281]
[EC 1.17.4.3 Transferred entry: 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase. As ferredoxin and not protein-disulfide is now known to take part in the reaction, the enzyme has been transferred to EC 1.17.7.1, (E)-4-hydroxy-3-methylbut-2-enyl-diphosphate synthase. (EC 1.17.4.3 created 2003, deleted 2009)]
Accepted name: (E)-4-hydroxy-3-methylbut-2-enyl-diphosphate synthase
Reaction: (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate + H2O + 2 oxidized ferredoxin = 2-C-methyl-D-erythritol 2,4-cyclodiphosphate + 2 reduced ferredoxin
For diagram of reaction, click here
Other name(s): 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase; (E)-4-hydroxy-3-methylbut-2-en-1-yl-diphosphate:protein-disulfide oxidoreductase (hydrating) (incorrect); (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase; GcpE
Systematic name: (E)-4-hydroxy-3-methylbut-2-en-1-yl-diphosphate:oxidized ferredoxin oxidoreductase
Comments: An iron-sulfur protein that contains a [4Fe-4S] cluster [1,2]. Forms, in the reverse direction, part of an alternative non-mevalonate pathway for isoprenoid biosynthesis that is found in most bacteria and in plant chloroplasts [4]. The enzyme from the plant Arabidopsis thaliana is active with photoreduced 5-deazaflavin but not with the flavodoxin/flavodoxin reductase/NADPH system that can be used as an electron donor by Escherichia coli [2]. Metabolites derived from isoprenoids play important roles in systems such as electron transport, photosynthesis, plant defense responses, hormonal regulation of development and membrane fluidity [1].
References:
1. Hecht, S., Eisenreich, W., Adam, P., Amslinger, S., Kis, K., Bacher, A., Arigoni, D. and Rohdich, F. Studies on the nonmevalonate pathway to terpenes: the role of the GcpE (IspG) protein. Proc. Natl. Acad. Sci. USA 98 (2001) 14837-14842. [PMID: 11752431]
2. Okada, K. and Hase, T. Cyanobacterial non-mevalonate pathway: (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase interacts with ferredoxin in Thermosynechococcus elongatus BP-1. J. Biol. Chem. 280 (2005) 20672-20679. [PMID: 15792953]
3. Seemann, M., Wegner, P., Schünemann, V., Bui, B.T.S., Wolff, M., Marquet, A., Trautwein, A.X. and Rohmer, M. Isoprenoid biosynthesis in chloroplasts via the methylerythritol phosphate pathway: the (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase (GcpE) from Arabidopsis thaliana is a [4Fe-4S] protein. J. Biol. Inorg. Chem. 10 (2005) 131-137. [PMID: 15650872]
4. Seemann, M., Bui, B.T.S., Wolff, M., Tritsch, D., Campos, N., Boronat, A., Marquet, A. and Rohmer, M. Isoprenoid biosynthesis through the methylerythritol phosphate pathway: the (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase (GcpE) is a [4Fe-4S] protein. Angew. Chem. Int. Ed. Engl. 41 (2002) 4337-4339. [PMID: 12434382]
5. Seemann, M., Bui, T.S.B., Wolff, M., Miginiac-Maslow, M. and Rohmer, M. Isoprenoid biosynthesis in plant chloroplasts via the MEP pathway: direct thylakoid/ferredoxin-dependent photoreduction of GcpE/IspG. FEBS Lett. 580 (2006) 1547-1552. [PMID: 16480720]
[EC 2.3.1.70 Deleted entry: CDP-acylglycerol O-arachidonoyltransferase. This enzyme was deleted following a retraction of the evidence upon which the entry had been drafted (Thompson, W. and Zuk, R.T. Acylation of CDP-monoacylglycerol cannot be confirmed. J. Biol. Chem. 258 (1983) 9623. [PMID: 6885763]). (EC 2.3.1.70 created 1984, deleted 2009)]
Accepted name: mannosylfructose-phosphate synthase
Reaction: GDP-mannose + D-fructose 6-phosphate = GDP + β-D-fructofuranosyl-α-D-mannopyranoside 6F-phosphate
Glossary: mannosylfructose = β-D-fructofuranosyl-α-D-mannopyranoside
Other name(s): mannosylfructose-6-phosphate synthase; MFPS
Systematic name: GDP-mannose:D-fructose-6-phosphate 2-α-D-mannosyltransferase
Comments: This enzyme, from the soil proteobacterium and plant pathogen Agrobacterium tumefaciens strain C58, requires Mg2+ or Mn2+ for activity. GDP-mannose can be replaced by ADP-mannose but with a concomitant decrease in activity. The product of this reaction is dephosphorylated by EC 3.1.3.79 (mannosylfructose-phosphate phosphatase) to form the nonreducing disaccharide mannosylfructose, which is the major endogenous osmolyte produced by several α-proteobacteria in response to osmotic stress. The F in the product name is used to indicate that the fructose residue of sucrose carries the substituent.
References:
1. Torres, L.L. and Salerno, G.L. A metabolic pathway leading to mannosylfructose biosynthesis in Agrobacterium tumefaciens uncovers a family of mannosyltransferases. Proc. Natl. Acad. Sci. USA 104 (2007) 14318–14323. [PMID: 17728402]
Accepted name: phosphoglycerol geranylgeranyltransferase
Reaction: geranylgeranyl diphosphate + sn-glycerol 1-phosphate = diphosphate + sn-3-O-(geranylgeranyl)glycerol 1-phosphate
For diagram of reaction, click here
Glossary: sn-glyceryl phosphate = sn-glycerol 1-phosphate = (S)-2,3-dihydroxypropyl dihydrogen phosphate
Other name(s): glycerol phosphate geranylgeranyltransferase; geranylgeranyl-transferase; prenyltransferase; (S)-3-O-geranylgeranylglyceryl phosphate synthase; (S)-geranylgeranylglyceryl phosphate synthase; GGGP synthase; (S)-GGGP synthase; GGGPS; geranylgeranyl diphosphate:sn-glyceryl phosphate geranylgeranyltransferase; geranylgeranyl diphosphate:sn-glycerol-1-phosphate geranylgeranyltransferase
Systematic name: geranylgeranyl-diphosphate:sn-glycerol-1-phosphate geranylgeranyltransferase
Comments: This cytosolic enzyme catalyses the first pathway-specific step in the biosynthesis of the core membrane diether lipids in archaebacteria [2]. Requires Mg2+ for maximal activity [2]. It catalyses the alkylation of the primary hydroxy group in sn-glycerol 1-phosphate by geranylgeranyl diphosphate (GGPP) in a prenyltransfer reaction where a hydroxy group is the nucleophile in the acceptor substrate [2]. The other enzymes involved in the biosynthesis of polar lipids in Archaea are EC 1.1.1.261 (sn-glycerol-1-phosphate dehydrogenase), EC 2.5.1.42 (geranylgeranylglycerol-phosphate geranylgeranyltransferase) and EC 2.7.7.67 (CDP-archaeol synthase), which lead to the formation of CDP-unsaturated archaeol. The final step in the pathway involves the addition of L-serine, with concomitant removal of CMP, leading to the production of unsaturated archaetidylserine [5].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number: 124650-69-7
References:
1. Zhang, D.-L., Daniels, L. and Poulter, C.D. Biosynthesis of archaebacterial membranes. Formation of isoprene ethers by a prenyl transfer reaction. J. Am. Chem. Soc. 112 (1990) 1264-1265.
2. Chen, A., Zhang, D. and Poulter, C.D. (S)-Geranylgeranylglyceryl phosphate synthase. Purification and characterization of the first pathway-specific enzyme in archaebacterial membrane lipid biosynthesis. J. Biol. Chem. 268 (1993) 21701-21705. [PMID: 8408023]
3. Nemoto, N., Oshima, T. and Yamagishi, A. Purification and characterization of geranylgeranylglyceryl phosphate synthase from a thermoacidophilic archaeon, Thermoplasma acidophilum. J. Biochem. 133 (2003) 651-657. [PMID: 12801917]
4. Payandeh, J., Fujihashi, M., Gillon, W. and Pai, E.F. The crystal structure of (S)-3-O-geranylgeranylglyceryl phosphate synthase reveals an ancient fold for an ancient enzyme. J. Biol. Chem. 281 (2006) 6070-6078. [PMID: 16377641]
5. Morii, H., Nishihara, M. and Koga, Y. CTP:2,3-di-O-geranylgeranyl-sn-glycero-1-phosphate cytidyltransferase in the methanogenic archaeon Methanothermobacter thermoautotrophicus. J. Biol. Chem. 275 (2000) 36568-36574. [PMID: 10960477]
Accepted name: geranylgeranylglycerol-phosphate geranylgeranyltransferase
Reaction: geranylgeranyl diphosphate + sn-3-O-(geranylgeranyl)glycerol 1-phosphate = diphosphate + 2,3-bis-O-(geranylgeranyl)glycerol 1-phosphate
For diagram of reaction, click here
Other name(s): geranylgeranyloxyglycerol phosphate geranylgeranyltransferase; geranylgeranyltransferase II; (S)-2,3-di-O-geranylgeranylglyceryl phosphate synthase; DGGGP synthase; DGGGPS
Systematic name: geranylgeranyl diphosphate:sn-3-O-(geranylgeranyl)glycerol 1-phosphate geranylgeranyltransferase
Comments: This enzyme is an integral-membrane protein that carries out the second prenyltransfer reaction involved in the formation of polar membrane lipids in Archaea. Requires a divalent metal cation, such as Mg2+ or Mn2+, for activity [2]. 4-Hydroxybenzoate, 1,4-dihydroxy 2-naphthoate, homogentisate and α-glycerophosphate cannot act as prenyl-acceptor substrates [2]. The other enzymes involved in the biosynthesis of polar lipids in Archaea are EC 1.1.1.261 (sn-glycerol-1-phosphate dehydrogenase), EC 2.5.1.41 (phosphoglycerol geranylgeranyltransferase), which, together with this enzyme, alkylates the hydroxy groups of glycerol 1-phosphate to yield unsaturated archaetidic acid, which is acted upon by EC 2.7.7.67 (CDP-archaeol synthase) to form CDP-unsaturated archaeol. The final step in the pathway involves the addition of L-serine, with concomitant removal of CMP, leading to the production of unsaturated archaetidylserine [3]. Belongs in the UbiA prenyltransferase family [2].
Links to other databases: BRENDA, ERGO, EXPASY, KEGG, CAS registry number: 124650-68-6
References:
1. Zhang, D.-L., Daniels, L. and Poulter, C.D. Biosynthesis of archaebacterial membranes. Formation of isoprene ethers by a prenyl transfer reaction. J. Am. Chem. Soc. 112 (1990) 1264-1265.
2. Hemmi, H., Shibuya, K., Takahashi, Y., Nakayama, T. and Nishino, T. (S)-2,3-Di-O-geranylgeranylglyceryl phosphate synthase from the thermoacidophilic archaeon Sulfolobus solfataricus. Molecular cloning and characterization of a membrane-intrinsic prenyltransferase involved in the biosynthesis of archaeal ether-linked membrane lipids. J. Biol. Chem. 279 (2004) 50197-50203. [PMID: 15356000]
3. Morii, H., Nishihara, M. and Koga, Y. CTP:2,3-di-O-geranylgeranyl-sn-glycero-1-phosphate cytidyltransferase in the methanogenic archaeon Methanothermobacter thermoautotrophicus. J. Biol. Chem. 275 (2000) 36568-36574. [PMID: 10960477]
Accepted name: hygromycin-B 7"-O-kinase
Reaction: ATP + hygromycin B = ADP + 7"-O-phosphohygromycin
For diagram click here
Other name(s): hygromycin B phosphotransferase; hygromycin-B kinase
Systematic name: ATP:hygromycin-B 7"-O-phosphotransferase
Comments: Phosphorylates the antibiotics hygromycin B, 1-N-hygromycin B and destomycin, but not hygromycin B2, at the 7"-hydroxy group in the destomic acid ring.
Links to other databases: BRENDA, EXPASY, KEGG, CAS registry number: 88361-67-5
References:
1. Zalacain, M., Pardo, J.M. and Jiménez, A. Purification and characterization of a hygromycin B phosphotransferase from Streptomyces hygroscopicus. Eur. J. Biochem. 162 (1987) 419-422. [PMID: 3026811]
Accepted name: CDP-archaeol synthase
Reaction: CTP + 2,3-bis-O-(geranylgeranyl)-sn-glycero-1-phosphate = diphosphate + CDP-2,3-bis-O-(geranylgeranyl)-sn-glycerol
For diagram of reaction, click here
Glossary: 2,3-bis-O-(geranylgeranyl)-sn-glycero-1-phosphate = 2,3-bis-O-(geranylgeranyl)-glycerophosphate ether = unsaturated archaetidic acid
CDP-archaeol = CDP-2,3-bis-O-(geranylgeranyl)-sn-glycerol
Other name(s): CDP-2,3-di-O-geranylgeranyl-sn-glycerol synthase; CTP:2,3-GG-GP ether cytidylyltransferase; CTP:2,3-di-O-geranylgeranyl-sn-glycero-1-phosphate cytidyltransferase
Systematic name: CTP:2,3-bis-O-(geranylgeranyl)-sn-glycero-1-phosphate cytidylyltransferase
Comments: This enzyme catalyses one of the steps in the biosynthesis of polar lipids in Archaea, which are characterized by having an sn-glycero-1-phosphate backbone rather than an sn-glycero-3-phosphate backbone as is found in bacteria and eukaryotes [1]. The enzyme requires Mg2+ and K+ for maximal activity [1]. The other enzymes involved in the biosynthesis of polar lipids in Archaea are EC 1.1.1.261 (sn-glycerol-1-phosphate dehydrogenase), EC 2.5.1.41 (phosphoglycerol geranylgeranyltransferase) and EC 2.5.1.42 (geranylgeranylglycerol-phosphate geranylgeranyltransferase), which together alkylate the hydroxy groups of glycerol 1-phosphate to give unsaturated archaetidic acid, which is acted upon by this enzyme to form CDP-unsaturated archaeol. The final step in the pathway involves the addition of L-serine, with concomitant removal of CMP, leading to the production of unsaturated archaetidylserine [1].
References:
1. Morii, H., Nishihara, M. and Koga, Y. CTP:2,3-di-O-geranylgeranyl-sn-glycero-1-phosphate cytidyltransferase in the methanogenic archaeon Methanothermobacter thermoautotrophicus. J. Biol. Chem. 275 (2000) 36568-36574. [PMID: 10960477]
2. Morii, H. and Koga, Y. CDP-2,3-di-O-geranylgeranyl-sn-glycerol:L-serine O-archaetidyltransferase (archaetidylserine synthase) in the methanogenic archaeon Methanothermobacter thermautotrophicus. J. Bacteriol. 185 (2003) 1181-1189. [PMID: 12562787]
Accepted name: mannosylfructose-phosphate phosphatase
Reaction: β-D-fructofuranosyl-α-D-mannopyranoside 6F-phosphate + H2O = β-D-fructofuranosyl-α-D-mannopyranoside + phosphate
Glossary: mannosylfructose = β-D-fructofuranosyl-α-D-mannopyranoside
Other name(s): mannosylfructose-6-phosphate phosphatase; MFPP
Systematic name: β-D-fructofuranosyl-α-D-mannopyranoside-6F-phosphate phosphohydrolase
Comments: This enzyme, from the soil proteobacterium and plant pathogen Agrobacterium tumefaciens strain C58, requires Mg2+ for activity. Mannosylfructose is the major endogenous osmolyte produced by several α-proteobacteria in response to osmotic stress and is synthesized by the sequential action of EC 2.4.1.246 (mannosylfructose-phosphate synthase) followed by this enzyme. While mannosylfructose 6-phosphate is the physiological substrate, the enzyme can use sucrose 6-phosphate very efficiently. The F in mannosylfructose 6F-phosphate is used to indicate that the fructose residue of sucrose carries the substituent.
References:
1. Torres, L.L. and Salerno, G.L. A metabolic pathway leading to mannosylfructose biosynthesis in Agrobacterium tumefaciens uncovers a family of mannosyltransferases. Proc. Natl. Acad. Sci. USA 104 (2007) 14318-14323. [PMID: 17728402]
Accepted name: geranylgeranyl diphosphate diphosphatase
Reaction: geranylgeranyl diphosphate + H2O = geranylgeraniol + diphosphate
For diagram click here.
glossary: plaunotol = 18-hydroxygeranylgeraniol
Other name(s): geranylgeranyl diphosphate phosphatase
Systematic name: geranyl-diphosphate diphosphohydrolase
Comments: Involved in the biosynthesis of plaunotol. There are two isoenzymes with different ion requirements. Neither require Mg2+ but in addition PII is inhibited by Zn2+, Mn2+ and Co2+. It is not known which isoenzyme is involved in plaunotol biosynthesis.
References:
1. Nualkaew, N., De-Eknamkul, W., Kutchan, T.M. and Zenk, M.H. Membrane-bound geranylgeranyl diphosphate phosphatases: purification and characterization from Croton stellatopilosus leaves. Phytochemistry 67 (2006) 1613-1620. [PMID: 16445953]
Accepted name: methanogen homoaconitase
Reaction: (R)-2-hydroxybutane-1,2,4-tricarboxylate + H2O = (1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate (overall reaction)
(1a) (R)-2-hydroxybutane-1,2,4-tricarboxylate = (Z)-but-1-ene-1,2,4-tricarboxylate + H2O
(1b) (Z)-but-1-ene-1,2,4-tricarboxylate + H2O = (1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate
Glossary: cis-homoaconitate = (Z)-but-1-ene-1,2,4-tricarboxylate
(R)-homocitrate = (R)-2-hydroxybutane-1,2,4-tricarboxylate
homoisocitrate = (-)-threo-homoisocitrate = (1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate
Other name(s): methanogen HACN
Systematic name: (R)-2-hydroxybutane-1,2,4-tricarboxylate hydro-lyase [(1R,2S)-1-hydroxybutane-1,2,4-tricarboxylate-forming]
Comments: This enzyme catalyses several reactions in the pathway of coenzyme-B biosynthesis in methanogenic archaea. Requires a [4Fe-4S] cluster for activity. In contrast to EC 4.2.1.36, homoaconitate hydratase, this enzyme can catalyse both the dehydration of (R)-homocitrate to form cis-homoaconitate and the subsequent hydration reaction that forms homoisocitrate. In addition to cis-homoaconitate, the enzyme can also catalyse the hydration of the physiological substrates dihomocitrate and trihomocitrate as well as the non-physiological substrate tetrahomocitrate. cis-Aconitate and threo-DL-isocitrate cannot act as substrates, and (S)-homocitrate and trans-homoaconitate act as inhibitors of the enzyme.
References:
1. Drevland, R.M., Jia, Y., Palmer, D.R. and Graham, D.E. Methanogen homoaconitase catalyzes both hydrolyase reactions in coenzyme B biosynthesis. J. Biol. Chem. 283 (2008) 28888-28896. [PMID: 18765671]
Accepted name: UDP-N-acetylglucosamine 4,6-dehydratase (inverting)
Reaction: UDP-N-acetylglucosamine = UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose + H2O
Glossary: pseudaminic acid = 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-α-l-manno-nonulosonic acid
Other name(s): FlaA1
Systematic name: UDP-N-acetylglucosamine hydro-lyase (inverting; UDP-2-acetamido-2,6-dideoxy-β-L-arabino-hex-4-ulose-forming)
Comments: Contains NADP+ as a cofactor. This is the first enzyme in the biosynthetic pathway of pseudaminic acid [3], a sialic-acid-like sugar that is unique to bacteria and is used by Helicobacter pylori to modify its flagellin. This enzyme plays a critical role in H. pylori's pathogenesis, being involved in the synthesis of both functional flagella and lipopolysaccharides [1,2]. It is completely inhibited by UDP-galactose. The reaction results in the chirality of the C-5 atom being inverted. It is thought that Lys-133 acts sequentially as a catalytic acid, protonating the C-6 hydroxy group and as a catalytic base, abstracting the C-5 proton, resulting in the elimination of water. This enzyme belongs to the short-chain dehydrogenase/reductase family of enzymes.
References:
1. Ishiyama, N., Creuzenet, C., Miller, W.L., Demendi, M., Anderson, E.M., Harauz, G., Lam, J.S. and Berghuis, A.M. Structural studies of FlaA1 from Helicobacter pylori reveal the mechanism for inverting 4,6-dehydratase activity. J. Biol. Chem. 281 (2006) 24489-24495. [PMID: 16651261]
2. Schirm, M., Soo, E.C., Aubry, A.J., Austin, J., Thibault, P. and Logan, S.M. Structural, genetic and functional characterization of the flagellin glycosylation process in Helicobacter pylori. Mol. Microbiol. 48 (2003) 1579-1592. [PMID: 12791140]
3. Schoenhofen, I.C., McNally, D.J., Brisson, J.R. and Logan, S.M. Elucidation of the CMP-pseudaminic acid pathway in Helicobacter pylori: synthesis from UDP-N-acetylglucosamine by a single enzymatic reaction. Glycobiology 16 (2006) 8C-14C. [PMID: 16751642]
Accepted name: α-bisabolene synthase
Reaction: (2E,6E)-farnesyl diphosphate = (E)-α-bisabolene + diphosphate
Other name(s): bisabolene synthase
Systematic name: (2E,6E)-farnesyl-diphosphate diphosphate-lyase [(E)-α-bisabolene-forming]
Comments: This cytosolic sesquiterpenoid synthase requires a divalent cation cofactor (Mg2+ or, to a lesser extent, Mn2+) to neutralize the negative charge of the diphosphate leaving group. While unlikely to encounter geranyl diphosphate (GDP) in vivo as it is localized to plastids, the enzyme can use GDP as a substrate in vitro to produce (+)-(4R)-limonene [cf. EC 4.2.3.20, (R)-limonene synthase]. The enzyme is induced as part of a defense mechanism in the grand fir Abies grandis as a response to stem wounding.
References:
1. Bohlmann, J., Crock, J., Jetter, R. and Croteau, R. Terpenoid-based defenses in conifers: cDNA cloning, characterization, and functional expression of wound-inducible (E)-α-bisabolene synthase from grand fir (Abies grandis). Proc. Natl. Acad. Sci. USA 95 (1998) 6756-6761. [PMID: 9618485]
Accepted name: epi-cedrol synthase
Reaction: (2E,6E)-farnesyl diphosphate + H2O = 8-epi-cedrol + diphosphate
Other name(s): 8-epicedrol synthase; epicedrol synthase
Systematic name: (2E,6E)-farnesyl-diphosphate diphosphate-lyase (8-epi-cedrol-forming)
Comments: The enzyme is activated by Mg2+ [2]. Similar to many other plant terpenoid synthases, this enzyme produces many products from a single substrate. The predominant product is the cyclic sesquiterpenoid alcohol, 8-epi-cedrol, with minor products including cedrol and the olefins α-cedrene, β-cedrene, (E)-β-farnesene and (E)-α-bisabolene [1].
References:
1. Mercke, P., Crock, J., Croteau, R. and Brodelius, P.E. Cloning, expression, and characterization of epi-cedrol synthase, a sesquiterpene cyclase from Artemisia annua L. Arch. Biochem. Biophys. 369 (1999) 213-222. [PMID: 10486140]
2. Hua, L. and Matsuda, S.P. The molecular cloning of 8-epicedrol synthase from Artemisia annua. Arch. Biochem. Biophys. 369 (1999) 208-212. [PMID: 10486139]
Accepted name: (Z)-γ-bisabolene synthase
Reaction: (2E,6E)-farnesyl diphosphate = (Z)-γ-bisabolene + diphosphate
Systematic name: (2E,6E)-farnesyl-diphosphate diphosphate-lyase [(Z)-γ-bisabolene-forming]
Comments: This sesquiterpenoid enzyme is constitutively expressed in the root, hydathodes and stigma of the plant Arabidopsis thaliana. If the leaves of the plant are wounded, e.g. by cutting, the enzyme is also induced close to the wound site. The sesquiterpenoids (E)-nerolidol and α-bisabolol are also produced by this enzyme as minor products.
References:
1. Ro, D.K., Ehlting, J., Keeling, C.I., Lin, R., Mattheus, N. and Bohlmann, J. Microarray expression profiling and functional characterization of AtTPS genes: duplicated Arabidopsis thaliana sesquiterpene synthase genes At4g13280 and At4g13300 encode root-specific and wound-inducible (Z)-γ-bisabolene synthases. Arch. Biochem. Biophys. 448 (2006) 104-116. [PMID: 16297850]
Accepted name: elisabethatriene synthase
Reaction: geranylgeranyl diphosphate = elisabethatriene + diphosphate
For reaction pathway click here and mechanism click here.
Other name(s): elisabethatriene cyclase
Systematic name: geranylgeranyl-diphosphate diphosphate-lyase (elisabethatriene-forming)
Comments: Requires Mg2+ or less efficiently Mn2+. The enzyme is also able to use farnesyl diphosphate and geranyl diphosphate.
Links to other databases: CAS registry number: 334022-59-2
References:
1. Kohl, A.C. and Kerr, R.G. Identification and characterization of the pseudopterosin diterpene cyclase, elisabethatriene synthase, from the marine gorgonian, Pseudopterogorgia elisabethae. Arch. Biochem. Biophys. 424 (2004) 97-104. [PMID: 15019841]
2. Bruck, T.B. and Kerr, R.G. Purification and kinetic properties of elisabethatriene synthase from the coral Pseudopterogorgia elisabethae. Comp. Biochem. Physiol. B Biochem. Mol. Biol. 143 (2006) 269-278. [PMID: 16423548]
Accepted name: aphidicolan-16β-ol synthase
Reaction: 9α-copalyl diphosphate + H2O = aphidicolan-16β-ol + diphosphate
For reaction pathway click here and mechanism click here.
Other name(s): PbACS
Systematic name: 9α-copalyl-diphosphate diphosphate-lyase (aphidicolan-16β-ol-forming)
Comment: This is a bifunctional enzyme which also has EC 5.5.1.14 syn-copalyl diphosphate synthase activity. Aphidicolan-16β-ol is a precursor of aphidicolin, a specific inhibitor of DNA polymerase α (EC 2.7.7.7).
References:
1. Oikawa, H., Toyomasu, T., Toshima, H., Ohashi, S., Kawaide, H., Kamiya, Y., Ohtsuka, M., Shinoda, S., Mitsuhashi, W. and Sassa, T. Cloning and functional expression of cDNA encoding aphidicolan-16 β-ol synthase: a key enzyme responsible for formation of an unusual diterpene skeleton in biosynthesis of aphidicolin. J. Am. Chem. Soc. 123 (2001) 5154-5155. [PMID: 11457369]
2. Toyomasu, T., Nakaminami, K., Toshima, H., Mie, T., Watanabe, K., Ito, H., Matsui, H., Mitsuhashi, W., Sassa T. and Oikawa, H. Cloning of a gene cluster responsible for the biosynthesis of diterpene aphidicolin, a specific inhibitor of DNA polymerase α. Biosci. Biotechnol. Biochem. 68 (2004) 146-152. [PMID: 14745177]
Accepted name: fusicocca-2,10(14)-diene synthase
Reaction: geranylgeranyl diphosphate = fusicocca-2,10(14)-diene + diphosphate
For reaction pathway click here and mechanism click here.
Other name(s): fusicoccadiene synthase; PaFS; PaDC4
Systematic name: geranylgeranyl diphosphate-lyase (fusicocca-2,10(14)-diene-forming)
Comment: A multifunctional enzyme with EC 2.5.1.29 farnesyltranstransferase activity.
References:
1. Toyomasu, T., Tsukahara, M., Kaneko, A., Niida, R., Mitsuhashi, W., Dairi, T., Kato, N. and Sassa, T. Fusicoccins are biosynthesized by an unusual chimera diterpene synthase in fungi. Proc. Natl. Acad. Sci. USA 104 (2007) 3084-3088. [PMID: 17360612]
Accepted name: isopimara-7,15-diene synthase
Reaction: copalyl diphosphate = isopimara-7,15-diene + diphosphate
For reaction pathway click here and mechanism click here.
Glossary: isopimara-7,15-diene = 13α-pimara-7,15-diene
Other name(s): PaTPS-Iso
Systematic name: copalyl diphosphate-lyase (isopimara-7,15-diene-forming)
Comment: The enzyme only gave isopimara-7,15-diene.
References:
Martin, D.M., Faldt, J. and Bohlmann, J. Functional characterization of nine Norway Spruce TPS genes and evolution of gymnosperm terpene synthases of the TPS-d subfamily. Plant Physiol. 135 (2004) 1908-1927. [PMID: 15310829]