additional information |
based on the sequence of a genomic fragment, caffeine demethylation enzyme system found in Pseudomonas sp. is predicted to consist of a two-component Rieske monooxygenases namely NdmA and NdmB specific towards methyl groups at 1 and 3 positions in xanthine ring respectively and one kind of three-component Rieske monooxygenase system comprising a monooxygenase NdmC specific towards 7-methylxanthine, a reductase component NdmD and a structural protein NdmE. NdmD also acts as the reductase component for NdmA and NdmB. The Rieske domain present in NdmD serves to function as an electron transfer domain during catalysis by NdmC as it lacks its own Rieske domain. NdmC forms a large multi-subunit complex comprising 2 monomeric units of each NdmC, NdmD, and NdmE and follows the typical electron flow pattern of Rieske oxygenases. The N-terminal Rieske domain found in NdmD is a product of domain shuffling between NdmC and NdmD during evolution and is not required for its reductase activity |
Pseudomonas sp. NCIM 5235 |
physiological function |
Pseudomonas sp. NCIM 5235 is a caffeine-degrading bacterial strain that metabolizes caffeine by sequential demethylation using methylxanthine demethylases, including 7-methylxanthine demethylase NdmC. These enzymes belong to the class of two-component Rieske oxygenases and require an oxidoreductase, NdmD, for efficient catalysis. Three oxygenases (NdmA, NdmB, and NdmC) specific towards methyl groups at 1, 3, and 7 positions in xanthine ring share a common reductase component, NdmD, analysis of NdmD parameters and function, overview. Another structural protein and oxidoreductase NdmE has also been shown to be required for catalysis by NdmC. Rieske oxygenases are an important class of enzymes that have been reported to play a major role in the degradation of xenobiotic compounds and drugs |
Pseudomonas sp. NCIM 5235 |