IUBMB Enzyme Nomenclature


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

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, 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.

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


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]

[EC created 2013]

Return to EC 1.14.13 home page
Return to EC 1.14 home page
Return to EC 1 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page