Biomaterial Database

Oxidative release of nitrite from 2-nitrotoluene by a three-component enzyme system from Pseudomonas sp. strain JS42. 1994

D An, and D T Gibson, and J C Spain

Department of Microbiology, University of Iowa, Iowa City 52242.

Pseudomonas sp. strain JS42 utilizes 2-nitrotoluene (2NT) as the sole source of carbon and energy for growth. Intact cells catalyze the oxidation of 2NT to 3-methylcatechol and nitrite in a reaction that requires molecular oxygen. Cell extracts oxidized 2NT to 3-methylcatechol and nitrite in the presence of NAD(P)H and ferrous iron. Ion-exchange chromatography yielded three protein fractions (A, B, and C) which were all required for the oxidation of 2NT to 3-methylcatechol and nitrite. Component B (reductase2NT) catalyzed a NAD(P)H-dependent reduction of cytochrome c. Solutions of component A (ISP2NT) were brown and showed absorption maxima at 458 and 324 nm. Two major bands with M(r)s 52,500 and 28,000 were observed when ISP2NT was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Component C could be replaced by ferredoxin NAP from the Pseudomonas putida NCIB 9816-4 naphthalene dioxygenase system and was given the designation ferredoxin2NT. Experiments with 18O2 showed that both oxygen atoms were added to the aromatic ring of 2NT to yield 3-methylcatechol. The enzyme is a new multicomponent enzyme system which we have designated 2NT 2,3-dioxygenase.

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009097	Multienzyme Complexes	Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.	Complexes, Multienzyme
D009245	NADH Dehydrogenase	A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.	NADH Cytochrome c Reductase,Diaphorase (NADH Dehydrogenase),NADH (Acceptor) Oxidoreductase,NADH Cytochrome c Oxidoreductase,Dehydrogenase, NADH
D009573	Nitrites	Salts of nitrous acid or compounds containing the group NO2-. The inorganic nitrites of the type MNO2 (where M	Nitrite
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D010105	Oxygenases	Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.	Oxygenase
D011549	Pseudomonas	A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.	Chryseomonas,Pseudomona,Flavimonas
D002396	Catechols	A group of 1,2-benzenediols that contain the general formula R-C6H5O2.	Pyrocatechols,o-Dihydroxybenzenes,ortho-Dihydroxybenzenes,o Dihydroxybenzenes,ortho Dihydroxybenzenes
D002852	Chromatography, Ion Exchange	Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.	Chromatography, Ion-Exchange,Ion-Exchange Chromatography,Chromatographies, Ion Exchange,Chromatographies, Ion-Exchange,Ion Exchange Chromatographies,Ion Exchange Chromatography,Ion-Exchange Chromatographies