EC |
1.14.13.178 |
Accepted name: |
methylxanthine N1-demethylase |
Reaction: |
(1) caffeine + O2 + NAD(P)H + H+ = theobromine + NAD(P)+ + H2O + formaldehyde (2) theophylline + O2 + NAD(P)H + H+ = 3-methylxanthine + NAD(P)+ + H2O + formaldehyde (3) paraxanthine + O2 + NAD(P)H + H+ = 7-methylxanthine + NAD(P)+ + H2O + formaldehyde |
Glossary: |
caffeine = 1,3,7-trimethylxanthine
theobromine = 3,7-dimethylxanthine
theophylline = 1,3-dimethylxanthine
paraxanthine = 1,7-dimethylxanthine
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Other name(s): |
ndmA (gene name) |
Systematic name: |
caffeine:oxygen oxidoreductase (N1-demethylating) |
Comments: |
A non-heme iron oxygenase. The enzyme from the bacterium Pseudomonas putida shares an NAD(P)H-FMN reductase subunit with EC 1.14.13.179, methylxanthine N3-demethylase, and has a 5-fold higher activity with NADH than with NADPH [2]. Also demethylate 1-methylxantine with lower efficiency. Forms part of the degradation pathway of methylxanthines. |
References: |
1. |
Summers, R.M., Louie, T.M., Yu, C.L. and Subramanian, M. Characterization of a broad-specificity non-haem iron N-demethylase from Pseudomonas putida CBB5 capable of utilizing several purine alkaloids as sole carbon and nitrogen source. Microbiology 157 (2011) 583–592. [PMID: 20966097] |
2. |
Summers, R.M., Louie, T.M., Yu, C.L., Gakhar, L., Louie, K.C. and Subramanian, M. Novel, highly specific N-demethylases enable bacteria to live on caffeine and related purine alkaloids. J. Bacteriol. 194 (2012) 2041–2049. [PMID: 22328667] |
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[EC 1.14.13.178 created 2013] |
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EC |
1.14.13.179 |
Accepted name: |
methylxanthine N3-demethylase |
Reaction: |
(1) theobromine + O2 + NAD(P)H + H+ = 7-methylxanthine + NAD(P)+ + H2O + formaldehyde (2) 3-methylxanthine + O2 + NAD(P)H + H+ = xanthine + NAD(P)+ + H2O + formaldehyde |
Glossary: |
theobromine = 3,7-dimethylxanthine
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Other name(s): |
ndmB (gene name) |
Systematic name: |
theobromine:oxygen oxidoreductase (N3-demethylating) |
Comments: |
A non-heme iron oxygenase. The enzyme from the bacterium Pseudomonas putida shares an NAD(P)H-FMN reductase subunit with EC 1.14.13.178, methylxanthine N1-demethylase, and has higher activity with NADH than with NADPH [1]. Also demethylates caffeine and theophylline with lower efficiency. Forms part of the degradation pathway of methylxanthines. |
References: |
1. |
Summers, R.M., Louie, T.M., Yu, C.L. and Subramanian, M. Characterization of a broad-specificity non-haem iron N-demethylase from Pseudomonas putida CBB5 capable of utilizing several purine alkaloids as sole carbon and nitrogen source. Microbiology 157 (2011) 583–592. [PMID: 20966097] |
2. |
Summers, R.M., Louie, T.M., Yu, C.L., Gakhar, L., Louie, K.C. and Subramanian, M. Novel, highly specific N-demethylases enable bacteria to live on caffeine and related purine alkaloids. J. Bacteriol. 194 (2012) 2041–2049. [PMID: 22328667] |
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[EC 1.14.13.179 created 2013] |
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EC |
1.17.5.2 |
Accepted name: |
caffeine dehydrogenase |
Reaction: |
caffeine + ubiquinone + H2O = 1,3,7-trimethylurate + ubiquinol |
Glossary: |
caffeine = 1,3,7-trimethylxanthine |
Systematic name: |
caffeine:ubiquinone oxidoreductase |
Comments: |
This enzyme, characterized from the soil bacterium Pseudomonas sp. CBB1, catalyses the incorporation of an oxygen atom originating from a water molecule into position C-8 of caffeine. It can also use theobromine as substrate. The enzyme utilizes short-tail ubiquinones as the preferred electron acceptor. |
References: |
1. |
Yu, C.L., Kale, Y., Gopishetty, S., Louie, T.M. and Subramanian, M. A novel caffeine dehydrogenase in Pseudomonas sp. strain CBB1 oxidizes caffeine to trimethyluric acid. J. Bacteriol. 190 (2008) 772–776. [PMID: 17981969] |
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[EC 1.17.5.2 created 2010] |
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EC |
2.1.1.159 |
Accepted name: |
theobromine synthase |
Reaction: |
S-adenosyl-L-methionine + 7-methylxanthine = S-adenosyl-L-homocysteine + 3,7-dimethylxanthine |
Glossary: |
theobromine = 3,7-dimethylxanthine
paraxanthine = 1,7-dimethylxanthine |
Other name(s): |
monomethylxanthine methyltransferase; MXMT; CTS1; CTS2; S-adenosyl-L-methionine:7-methylxanthine 3-N-methyltransferase |
Systematic name: |
S-adenosyl-L-methionine:7-methylxanthine N3-methyltransferase |
Comments: |
This is the third enzyme in the caffeine-biosynthesis pathway. This enzyme can also catalyse the conversion of paraxanthine into caffeine, although the paraxanthine pathway is considered to be a minor pathway for caffeine biosynthesis [2,3]. |
References: |
1. |
Ogawa, M., Herai, Y., Koizumi, N., Kusano, T. and Sano, H. 7-Methylxanthine methyltransferase of coffee plants. Gene isolation and
enzymatic properties. J. Biol. Chem. 276 (2001) 8213–8218. [PMID: 11108716] |
2. |
Uefuji, H., Ogita, S., Yamaguchi, Y., Koizumi, N. and Sano, H. Molecular cloning and functional characterization of three distinct
N-methyltransferases involved in the caffeine biosynthetic pathway in
coffee plants. Plant Physiol. 132 (2003) 372–380. [PMID: 12746542] |
3. |
Yoneyama, N., Morimoto, H., Ye, C.X., Ashihara, H., Mizuno, K. and Kato, M. Substrate specificity of N-methyltransferase involved in purine alkaloids synthesis is dependent upon one amino acid residue of the enzyme. Mol. Genet. Genomics 275 (2006) 125–135. [PMID: 16333668] |
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[EC 2.1.1.159 created 2007] |
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EC |
2.1.1.160 |
Accepted name: |
caffeine synthase |
Reaction: |
(1) S-adenosyl-L-methionine + 3,7-dimethylxanthine = S-adenosyl-L-homocysteine + 1,3,7-trimethylxanthine (2) S-adenosyl-L-methionine + 1,7-dimethylxanthine = S-adenosyl-L-homocysteine + 1,3,7-trimethylxanthine (3) S-adenosyl-L-methionine + 7-methylxanthine = S-adenosyl-L-homocysteine + 3,7-dimethylxanthine |
Glossary: |
theobromine = 3,7-dimethylxanthine
paraxanthine = 1,7-dimethylxanthine
caffeine = 1,3,7-trimethylxanthine |
Other name(s): |
dimethylxanthine methyltransferase; 3N-methyltransferase; DXMT; CCS1; S-adenosyl-L-methionine:3,7-dimethylxanthine 1-N-methyltransferase |
Systematic name: |
S-adenosyl-L-methionine:3,7-dimethylxanthine N1-methyltransferase |
Comments: |
Paraxanthine is the best substrate for this enzyme but the paraxanthine pathway is considered to be a minor pathway for caffeine biosynthesis [2,3]. |
References: |
1. |
Kato, M., Mizuno, K., Fujimura, T., Iwama, M., Irie, M., Crozier, A. and Ashihara, H. Purification and characterization of caffeine synthase from tea leaves. Plant Physiol. 120 (1999) 579–586. [PMID: 10364410] |
2. |
Mizuno, K., Okuda, A., Kato, M., Yoneyama, N., Tanaka, H., Ashihara, H. and Fujimura, T. Isolation of a new dual-functional caffeine synthase gene encoding an enzyme for the conversion of 7-methylxanthine to caffeine from coffee (Coffea arabica L.). FEBS Lett. 534 (2003) 75–81. [PMID: 12527364] |
3. |
Uefuji, H., Ogita, S., Yamaguchi, Y., Koizumi, N. and Sano, H. Molecular cloning and functional characterization of three distinct
N-methyltransferases involved in the caffeine biosynthetic pathway in
coffee plants. Plant Physiol. 132 (2003) 372–380. [PMID: 12746542] |
4. |
Kato, M., Mizuno, K., Crozier, A., Fujimura, T. and Ashihara, H. Caffeine synthase gene from tea leaves. Nature 406 (2000) 956–957. [PMID: 10984041] |
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[EC 2.1.1.160 created 2007] |
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