Alkane 1 monooxygenase. Medical search

The generic name for the group of aliphatic hydrocarbons Cn-H2n+2. They are denoted by the suffix -ane. (Grant & Hackh's Chemical Dictionary, 5th ed)

A P450 oxidoreductase that catalyzes the hydroxylation of the terminal carbon of linear hydrocarbons such as octane and FATTY ACIDS in the omega position. The enzyme may also play a role in the oxidation of a variety of structurally unrelated compounds such as XENOBIOTICS, and STEROIDS.

Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.

Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.

An NADPH-dependent flavin monooxygenase that plays a key role in the catabolism of TRYPTOPHAN by catalyzing the HYDROXYLATION of KYNURENINE to 3-hydroxykynurenine. It was formerly characterized as EC 1.14.1.2 and EC 1.99.1.5.

A family of gram-negative, aerobic bacteria utilizing only one-carbon organic compounds and isolated from in soil and water.

A species of METHYLOCOCCUS which forms capsules and is capable of autotrophic carbon dioxide fixation. (From Bergey's Manual of Determinative Bacteriology, 9th ed)

A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.

Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.

A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.

Naturally occurring complex liquid hydrocarbons which, after distillation, yield combustible fuels, petrochemicals, and lubricants.

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).

A bacterial genus of the order ACTINOMYCETALES.

A species of METHYLOSINUS which is capable of degrading trichloroethylene and other organic pollutants.

Eight-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives.

A soluble cytochrome P-450 enzyme that catalyzes camphor monooxygenation in the presence of putidaredoxin, putidaredoxin reductase, and molecular oxygen. This enzyme, encoded by the CAMC gene also known as CYP101, has been crystallized from bacteria and the structure is well defined. Under anaerobic conditions, this enzyme reduces the polyhalogenated compounds bound at the camphor-binding site.

A class of iron-sulfur proteins that contains one iron coordinated to the sulfur atom of four cysteine residues. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)

Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)

The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)

Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)

A genus of gram-negative, ellipsoidal or rod-shaped bacteria whose major source of energy and reducing power is from the oxidation of ammonia to nitrite. Its species occur in soils, oceans, lakes, rivers, and sewage disposal systems.

A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)

A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

A genus of gram-positive BACTERIA in the family Gordoniaceae, isolated from soil and from sputa of patients with chest disorders. It is also used for biotransformation of natural products.

A benzyl-indazole having analgesic, antipyretic, and anti-inflammatory effects. It is used to reduce post-surgical and post-traumatic pain and edema and to promote healing. It is also used topically in treatment of RHEUMATIC DISEASES and INFLAMMATION of the mouth and throat.

An enzyme that catalyzes the conversion of L-tyrosine, tetrahydrobiopterin, and oxygen to 3,4-dihydroxy-L-phenylalanine, dihydrobiopterin, and water. EC 1.14.16.2.

The second enzyme in the committed pathway for CHOLESTEROL biosynthesis, this enzyme catalyzes the first oxygenation step in the biosynthesis of STEROLS and is thought to be a rate limiting enzyme in this pathway. Specifically, this enzyme catalyzes the conversion of SQUALENE to (S)-squalene-2,3-epoxide.

The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)

A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.

An enzyme that utilizes NADH or NADPH to reduce FLAVINS. It is involved in a number of biological processes that require reduced flavin for their functions such as bacterial bioluminescence. Formerly listed as EC 1.6.8.1 and EC 1.5.1.29.

A flavoprotein that catalyzes the reduction of heme-thiolate-dependent monooxygenases and is part of the microsomal hydroxylating system. EC 1.6.2.4.

These enzymes catalyze the elimination of ammonia from amidines with the formation of a double bond. EC 4.3.2.

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.

Derivatives of the dimethylisoalloxazine (7,8-dimethylbenzo[g]pteridine-2,4(3H,10H)-dione) skeleton. Flavin derivatives serve an electron transfer function as ENZYME COFACTORS in FLAVOPROTEINS.

A large group of aerobic bacteria which show up as pink (negative) when treated by the gram-staining method. This is because the cell walls of gram-negative bacteria are low in peptidoglycan and thus have low affinity for violet stain and high affinity for the pink dye safranine.

A family of halophilic bacteria in the order Oceanospirillales. Its principal carbon and energy sources are linear-chain ALKANES and their derivatives.

An antiseptic and disinfectant aromatic alcohol.

A highly volatile inhalation anesthetic used mainly in short surgical procedures where light anesthesia with good analgesia is required. It is also used as an industrial solvent. Prolonged exposure to high concentrations of the vapor can lead to cardiotoxicity and neurological impairment.

A widely used industrial solvent.

Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.

The rate dynamics in chemical or physical systems.

A family of gram-negative methanotrophs in the order Rhizobiales, distantly related to the nitrogen-fixing and phototrophic bacteria.

The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

Hydrocarbon compounds with one or more of the hydrogens replaced by CHLORINE.

A plastic substance deposited by insects or obtained from plants. Waxes are esters of various fatty acids with higher, usually monohydric alcohols. The wax of pharmacy is principally yellow wax (beeswax), the material of which honeycomb is made. It consists chiefly of cerotic acid and myricin and is used in making ointments, cerates, etc. (Dorland, 27th ed)

A family of aerobic gram-negative rods that are nitrogen fixers. They are highly viscous, and appear as a semitransparent slime in giant colonies.

Alkyl compounds containing a hydroxyl group. They are classified according to relation of the carbon atom: primary alcohols, R-CH2OH; secondary alcohols, R2-CHOH; tertiary alcohols, R3-COH. (From Grant & Hackh's Chemical Dictionary, 5th ed)

The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)

Drug metabolizing enzymes which oxidize methyl ethers. Usually found in liver microsomes.

A drug-metabolizing enzyme found in the hepatic, placental and intestinal microsomes that metabolizes 7-alkoxycoumarin to 7-hydroxycoumarin. The enzyme is cytochrome P-450- dependent.

A species of gram-negative bacteria in the genus PSEUDOMONAS, which is found in SOIL and WATER.

Phenols substituted with one or more chlorine atoms in any position.

A genus of gram-negative bacteria of the family MORAXELLACEAE, found in soil and water and of uncertain pathogenicity.

The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.

The functional hereditary units of BACTERIA.

Proteins found in any species of bacterium.

Compounds used extensively as acetylation, oxidation and dehydrating agents and in the modification of proteins and enzymes.

A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.

Toxic chlorinated unsaturated hydrocarbons. Include both the 1,1- and 1,2-dichloro isomers. Both isomers are toxic, but 1,1-dichloroethylene is the more potent CNS depressant and hepatotoxin. It is used in the manufacture of thermoplastic polymers.

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.

Organic compounds containing carbon and hydrogen in the form of an unsaturated, usually hexagonal ring structure. The compounds can be single ring, or double, triple, or multiple fused rings.

A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.

The relationships of groups of organisms as reflected by their genetic makeup.

A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)

A species of gram-negative bacteria in the genus PSEUDOMONAS, containing multiple genomovars. It is distinguishable from other pseudomonad species by its ability to use MALTOSE and STARCH as sole carbon and energy sources. It can degrade ENVIRONMENTAL POLLUTANTS and has been used as a model organism to study denitrification.

A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.

Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)

A species of nonpathogenic fluorescent bacteria found in feces, sewage, soil, and water, and which liquefy gelatin.

Deoxyribonucleic acid that makes up the genetic material of bacteria.

A colorless liquid used as a solvent and an antiseptic. It is one of the ketone bodies produced during ketoacidosis.

A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.

An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.

8-Hydroxyquinolinols chlorinated on the number 5 and/or 7 carbon atom(s). They are antibacterial, antiprotozoal, and antidiarrheal, especially in amebiasis, and have also been used as antiseborrheics. The compounds are mostly used topically, but have been used also as animal feed additives. They may cause optic and other neuropathies and are most frequently administered in combination with other agents.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.

An enzyme that catalyzes the hydroxylation of TRYPTOPHAN to 5-HYDROXYTRYPTOPHAN in the presence of NADPH and molecular oxygen. It is important in the biosynthesis of SEROTONIN.

A genus of saprobic mushrooms in the family Bolbitiaceae that grow in grass, dung, garden mulch, or in woods.

Organic compounds that include a cyclic ether with three ring atoms in their structure. They are commonly used as precursors for POLYMERS such as EPOXY RESINS.

The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.

A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.

Compounds in which one or more of the three hydroxyl groups of glycerol are in ethereal linkage with a saturated or unsaturated aliphatic alcohol; one or two of the hydroxyl groups of glycerol may be esterified. These compounds have been found in various animal tissue.

A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues.

A flavoprotein that catalyzes the synthesis of protocatechuic acid from 4-hydroxybenzoate in the presence of molecular oxygen. EC 1.14.13.2.

Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.

Rhodium. A hard and rare metal of the platinum group, atomic number 45, atomic weight 102.905, symbol Rh. (Dorland, 28th ed)

An enzyme that catalyzes the oxidation of BENZOATE to 4-hydroxybenzoate. It requires IRON and tetrahydropteridine.

The PalkBFGHJKL promoter is under carbon catabolite repression control in Pseudomonas oleovorans but not in Escherichia coli alk+ recombinants. (1/260)

The alk genes are located on the OCT plasmid of Pseudomonas oleovorans and encode an inducible pathway for the utilization of n-alkanes as carbon and energy sources. We have investigated the influence of alternative carbon sources on the induction of this pathway in P. oleovorans and Escherichia coli alk+ recombinants. In doing so, we confirmed earlier reports that induction of alkane hydroxylase activity in pseudomonads is subject to carbon catabolite repression. Specifically, synthesis of the monooxygenase component AlkB is repressed at the transcriptional level. The alk genes have been cloned into plasmid pGEc47, which has a copy number of about 5 to 10 per cell in both E. coli and pseudomonads. Pseudomonas putida GPo12 is a P. oleovorans derivative cured of the OCT plasmid. Upon introduction of pGEc47 in this strain, carbon catabolite repression of alkane hydroxylase activity was reduced significantly. In cultures of recombinant E. coli HB101 and W3110 carrying pGEc47, induction of AlkB and transcription of the alkB gene were no longer subject to carbon catabolite repression. This suggests that carbon catabolite repression of alkane degradation is regulated differently in Pseudomonas and in E. coli strains. These results also indicate that PalkBFGHJKL, the Palk promoter, might be useful in attaining high expression levels of heterologous genes in E. coli grown on inexpensive carbon sources which normally trigger carbon catabolite repression of native expression systems in this host. (+info)

Characterization of cytochrome P450 expression in human oesophageal mucosa. (2/260)

The expression of cytochrome (CYP) P450 enzymes in human oesophageal mucosa was investigated in a total of 25 histologically non-neoplastic surgical tissue specimens by using specific antibodies in immunoblots and by RT-PCR mRNA analysis. The presence of CYP1A, 2E1, 3A and 4A enzymes was demonstrated by both techniques; CYP2A reactive protein was also detected by immunoblot. The presence of CYP4B1 mRNA was established but no specific antibody was available for detection of the corresponding protein by immunoblot. CYP2B6/7 mRNA was not detected in any sample. The mRNA transcripts for CYP1A1, 2E1, 4A11 and 4B1 were consistently detected in the majority of samples (>84%), whereas CYP1A2 mRNA was only detected in 11 of 19 specimens examined. An RT-PCR method to differentiate CYP3A4 and 3A5 mRNA was developed. This demonstrated CYP3A5 mRNA expression in all samples tested, whereas CYP3A4 mRNA was not detectable, suggesting that CYP3A5 is the major CYP3A protein in human oesophagus. There were significant interindividual variations in the amount of proteins, ranging from 8-fold for CYP4A to 43-fold for CYP2E1. For each patient, data on exposure to risk factors for oesophageal cancer were available, including tobacco smoke, alcohol, gastro-oesophageal reflux and hot beverage consumption. None of these risk factors or other patient characteristics (age, sex, tumour location and tumour stage) were correlated with the protein level of the individual CYP enzymes as determined by quantitation of immunoblot staining. However, the small series of samples precludes any strong conclusion concerning the lack of such correlations. There were no differences between squamous cell carcinomas and adenocarcinomas in either the qualitative or quantitative expression of the CYP enzymes. These data demonstrate that a range of CYP enzymes are expressed in human oesophageal mucosa and indicate that this tissue has the capacity to activate chemical carcinogens to reactive DNA binding metabolites. (+info)

Role of the alternative sigma factor sigmaS in expression of the AlkS regulator of the Pseudomonas oleovorans alkane degradation pathway. (3/260)

The AlkS protein activates transcription from the PalkB promoter, allowing the expression of a number of genes required for the assimilation of alkanes in Pseudomonas oleovorans. We have identified the promoter from which the alkS gene is transcribed, PalkS, and analyzed its expression under different conditions and genetic backgrounds. Transcription from PalkS was very low during the exponential phase of growth and increased considerably when cells reached the stationary phase. The PalkS -10 region was similar to the consensus described for promoters recognized by Escherichia coli RNA polymerase bound to the alternative sigma factor sigmaS, which directs the expression of many stationary-phase genes. Reporter strains containing PalkS-lacZ transcriptional fusions showed that PalkS promoter is very weakly expressed in a Pseudomonas putida strain bearing an inactivated allele of the gene coding for sigmaS, rpoS. When PalkS was transferred to E. coli, transcription started at the same site and expression was higher in stationary phase only if sigmaS-RNA polymerase was present. The low levels of AlkS protein generated in the absence of sigmaS were enough to support a partial induction of the PalkB promoter. The -10 and -35 regions of PalkS promoter also show some similarity to the consensus recognized by sigmaD-RNA polymerase, the primary form of RNA polymerase. We propose that in exponential phase PalkS is probably recognized both by sigmaD-RNA polymerase (inefficiently) and by sigmaS-RNA polymerase (present at low levels), leading to low-level expression of the alkS gene. sigmaS-RNA polymerase would be responsible for the high level of activity of PalkS observed in stationary phase. (+info)

Insulin differentially affects xenobiotic-enhanced, cytochrome P-450 (CYP)2E1, CYP2B, CYP3A, and CYP4A expression in primary cultured rat hepatocytes. (4/260)

Uncontrolled diabetes results in enhanced expression of cytochrome P-450 (CYP)2E1, CYP2B, CYP3A, and CYP4A. Because of the simultaneous and confounding metabolic and hormonal changes that occur in vivo as a consequence of diabetes, primary cultured rat hepatocytes provide an excellent model system for examination of the effects of insulin on P-450 expression and on xenobiotic-mediated P-450 expression. In the present study, we examined the effects of insulin on pyridine-, phenobarbital-, and ciprofibrate-mediated expression of CYP2E1, CYP2B, CYP3A, and CYP4A in primary cultured rat hepatocytes. Pyridine addition to primary rat hepatocytes cultured in the presence of 1 nM insulin or in the absence of insulin resulted in a 3.5-fold and 3-fold enhancement in CYP2E1 protein expression, respectively, in the absence of any pyridine-mediated increase in mRNA expression. In contrast, hepatocytes cultured in the standard concentration of 1 microM insulin resulted in only a 2-fold increase in protein expression. Thus, the fold-induction of CYP2E1 protein in response to pyridine was 1.5- to 1.8-fold greater in either the absence of insulin or in the presence of 1 nM insulin, respectively, than that monitored in the presence of 1 microM insulin. To examine whether insulin effects on xenobiotic-mediated CYP2E1 expression were selective, insulin effects on xenobiotic-mediated expression of transcriptionally regulated CYP2B, CYP3A, and CYP4A were examined. Pyridine- or phenobarbital-mediated induction of CYP2B mRNA and protein expression in hepatocytes was suppressed by as much as 80% at lower insulin levels (0 and 1 nM), relative to the level monitored in the presence of 1 microM insulin. Omitting insulin from the medium resulted in a 50% decrease in CYP3A mRNA levels in response to phenobarbital treatment and a 30% decrease in CYP4A mRNA levels in response to ciprofibrate treatment, relative to the level obtained in response to these treatments in the presence of 1 microM insulin. The results of this study demonstrate that decreasing the insulin level in the primary hepatocyte culture medium enhanced xenobiotic-mediated CYP2E1 expression, whereas lower insulin levels suppressed xenobiotic-mediated CYP2B, CYP3A, and CYP4A expression in this cell culture system. (+info)

Hypoxia-induced production of 12-hydroxyeicosanoids in the corneal epithelium: involvement of a cytochrome P-4504B1 isoform. (5/260)

The corneal epithelium metabolizes arachidonic acid by a cytochrome P-450 (CYP)-mediated activity to 12-hydroxy-5,8,11, 14-eicosatetraenoic acid (12(R)-HETE) and 12-hydroxy-5,8, 14-eicosatrienoic acid (12(R)-HETrE ). Both metabolites possess potent inflammatory properties, with 12(R)-HETrE being a powerful angiogenic factor, and they assume the role of inflammatory mediators in hypoxia- and chemical-induced injury in the cornea in vivo and in vitro. We used a model of corneal organ culture that exhibits hypoxia-induced epithelial CYP-dependent 12(R)-HETE and 12(R)-HETrE synthesis for isolating, identifying, and characterizing the CYP protein responsible for these eicosanoid syntheses. Northern analysis revealed the presence of a CYP4A-hybridizable mRNA, the levels of which were increased after hypoxia. Reverse transcription-polymerase chain reaction analysis with primers specific for the CYP4A family led to the isolation of a 671-base pair fragment with a 98.8% sequence homology to the rabbit lung CYP4B1 isoform, of which the levels in the corneal epithelium were greatly increased under hypoxic conditions. Moreover, phenobarbital, an inducer of hepatic CYP4B1 in the rabbit, also induced 12-HETE and 12-HETrE synthesis. Antibodies against CYP4B1, but not against CYP4A1, inhibited hypoxia-, clofibrate-, and phenobarbital-induced 12-HETE and 12-HETrE synthesis. These results suggest the involvement of a CYP4B1 isoform in the corneal epithelial synthesis of these eicosanoids in response to hypoxia. (+info)

Arachidonic acid and PGE2 regulation of hepatic lipogenic gene expression. (6/260)

N-6 polyunsaturated fatty acids (PUFA) suppress hepatic and adipocyte de novo lipogenesis by inhibiting the transcription of genes encoding key lipogenic proteins. In cultured 3T3-L1 adipocytes, arachidonic acid (20:4,n-6) suppression of lipogenic gene expression requires cyclooxygenase (COX) activity. In this study, we found no evidence to support a role for COX-1 or -2 in the 20:4,n-6 inhibition of hepatocyte lipogenic gene expression. In contrast to L1 preadipocytes, adipocytes and rat liver, RT-PCR and Western analyses did not detect COX-1 or COX-2 expression in cultured primary hepatocytes. Moreover, the COX inhibitor, flurbiprofen, did not affect the 20:4,n-6 regulation of lipogenic gene expression in primary hepatocytes. Despite the absence of COX-1 and -2 expression in primary hepatocytes, prostaglandins (PGE2 and PGF2alpha) suppressed fatty acid synthase, l-pyruvate kinase, and the S14 protein mRNA, while having no effect on acyl-CoA oxidase or CYP4A2 mRNA. Using PGE2 receptor agonist, the PGE2 effect on lipogenic gene expression was linked to EP3 receptors. PGE2 inhibited S14CAT activity in transfected primary hepatocytes and targeted the S14 PUFA-response region located -220 to -80 bp upstream from the transcription start site. Taken together, these studies show that COX-1 and COX-2 do not contribute to the n-6 PUFA suppression of hepatocyte lipogenic gene expression. However, cyclooxygenase products from non-parenchymal cells can act on parenchymal cells through a paracrine process and mimic the effects of n-6 PUFA on lipogenic gene expression. (+info)

Kinetic profile of the rat CYP4A isoforms: arachidonic acid metabolism and isoform-specific inhibitors. (7/260)

20-Hydroxyeicosatetraenoic acid (HETE), the cytochrome P-450 (CYP) 4A omega-hydroxylation product of arachidonic acid, has potent biological effects on renal tubular and vascular functions and on the control of arterial pressure. We have expressed high levels of the rat CYP4A1, -4A2, -4A3, and -4A8 cDNAs, using baculovirus and Sf 9 insect cells. Arachidonic acid omega- and omega-1-hydroxylations were catalyzed by three of the CYP4A isoforms; the highest catalytic efficiency of 947 nM-1. min-1 for CYP4A1 was followed by 72 and 22 nM-1. min-1 for CYP4A2 and CYP4A3, respectively. CYP4A2 and CYP4A3 exhibited an additional arachidonate 11,12-epoxidation activity, whereas CYP4A1 operated solely as an omega-hydroxylase. CYP4A8 did not catalyze arachidonic or linoleic acid but did have a detectable lauric acid omega-hydroxylation activity. The inhibitory activity of various acetylenic and olefinic fatty acid analogs revealed differences and indicated isoform-specific inhibition. These studies suggest that CYP4A1, despite its low expression in extrahepatic tissues, may constitute the major source of 20-HETE synthesis. Moreover, the ability of CYP4A2 and -4A3 to catalyze the formation of two opposing biologically active metabolites, 20-HETE and 11, 12-epoxyeicosatrienoic acid, may be of great significance to the regulation of vascular tone. (+info)

Regulation of P-450 4A activity in the glomerulus of the rat. (8/260)

We recently reported that an enzyme of the cytochrome P-450 4A family is expressed in the glomerulus, but there is no evidence that 20-hydroxyeicosatetraenoic acid (20-HETE) can be produced by this tissue. The purpose of present study was to determine whether glomeruli isolated from the kidney of rats can produce 20-HETE and whether the production of this metabolite is regulated by nitric oxide (NO) and dietary salt intake. Isolated glomeruli produced 20-HETE, dihydroxyeicosatrienoic acids, and 12-hydroxyeicosatetraenoic acid (4.13 +/- 0.38, 4.20 +/- 0.38, and 2. 10 +/- 0.20 pmol. min-1. mg protein-1, respectively) when incubated with arachidonic acid (10 microM). The formation of 20-HETE was dependent on the availability of NADPH and the PO2 of the incubation medium. The formation of 20-HETE was inhibited by NO donors in a concentration-dependent manner. The production of 20-HETE was greater in glomeruli isolated from the kidneys of rats fed a low-salt diet than in kidneys of rats fed a high-salt diet (5.67 +/- 0.32 vs. 2.83 +/- 0.32 pmol. min-1. mg protein-1). Immunoblot experiments indicated that the expression of P-450 4A protein in glomeruli from the kidneys of rats fed a low-salt diet was sixfold higher than in kidneys of rats fed a high-salt diet. These results indicate that arachidonic acid is primarily metabolized to 20-HETE and dihydroxyeicosatrienoic acids in glomeruli and that glomerular P-450 activity is modulated by NO and dietary salt intake. (+info)

... alkane monooxygenase, 1-hydroxylase, AlkB, and alkane hydroxylase. It contains a diiron non-heme active site. McKenna EJ, Coon ... In enzymology, an alkane 1-monooxygenase (EC 1.14.15.3) is an enzyme that catalyzes the chemical reactions an alkane + reduced ... Alkanes of 6 to 22 carbons have been observed as substrates. This enzyme belongs to the family of oxidoreductases, specifically ... The systematic name of this enzyme class is alkane, reduced-rubredoxin:oxygen 1-oxidoreductase. Other names in common use ...

https://en.wikipedia.org/wiki/Alkane_1-monooxygenase

... camphor 5-monooxygenase MeSH D08.811.682.690.708.170.500 - alkane 1-monooxygenase MeSH D08.811.682.690.708.170.915 - steroid ... 4-hydroxybenzoate 3-monooxygenase MeSH D08.811.682.690.708.557 - kynurenine 3-monooxygenase MeSH D08.811.682.690.708.601 - ... trans-cinnamate 4-monooxygenase MeSH D08.622.509.700 - pepsinogen a MeSH D08.622.509.725 - pepsinogen c MeSH D08.622.610.500 - ... monophenol monooxygenase MeSH D08.811.682.690.708.170 - cytochrome p-450 enzyme system MeSH D08.811.682.690.708.170.040 - aryl ...

https://en.wikipedia.org/wiki/List_of_MeSH_codes_(D08)

... alkane, reduced-rubredoxin:oxygen 1-oxidoreductase) octane + reduced rubredoxin + O2 = 1-octanol + oxidized rubredoxin + H2O EC ... 2-monooxygenase [(+)-camphor, reduced-rubredoxin:oxygen oxidoreductase (1,2-lactonizing)] (+)-bornane-2,5-dione + reduced ... 1] The lower Fe2+ cation change of the reduced state leaves a higher negative charge on the Cys 9 Sγ-donor which attracts water ... rubredoxin + O2 = 5-oxo-1,2-campholide + oxidized rubredoxin + H2O EC 1.14.15.3 alkane 1-monooxygenase ( ...

https://en.wikipedia.org/wiki/Rubredoxin

The n-alkanes are oxidized by monooxygenase to secondary alcohols, then to ketones and finally to fatty acids. R 1 − ( CH 2 ... linear alkanes branched alkanes > small aromatics > cyclic alkanes. Some compounds, such as the high molecular weight ... From the oxidation of the methyl group of n-alkanes by the alkane hydroxylase, n-alkanols are released which are further ... where toluene is converted into o-cresol by toluene 2-monooxygenase and subsequently another monooxygenase converts it to 3- ...

https://en.wikipedia.org/wiki/Hydrocarbonoclastic_bacteria

... olei to utilize petroleum hydrocarbons in farmland soil can be explained by its lack of alkane monooxygenase and aromatic ring- ... 1-13. ISBN 978-1-118-96060-8. Yabuuchi, E.; T. Kaneko; I. Yano; C.W. Moss; N. Miyoshi. (1 July 1983). "Sphingobacterium gen. ... Liu, Bin; Yang, Xiaojun; Sheng, Mengyao; Yang, Zhou; Qiu, Jiguo; Wang, Chenghong; He, Jian (1 March 2020). "Sphingobacterium ... 1 June 2017). "Sphingobacterium alkalisoli sp. nov., isolated from a saline-alkaline soil". International Journal of Systematic ...

https://en.wikipedia.org/wiki/Sphingobacterium_olei

Rasche ME, Hicks RE, Hyman MR, Arp DJ (September 1990). "Oxidation of monohalogenated ethanes and n-chlorinated alkanes by ... "Evidence that particulate methane monooxygenase and ammonia monooxygenase may be evolutionarily related". FEMS Microbiology ... Ammonia+monooxygenase at the US National Library of Medicine Medical Subject Headings (MeSH) Portal: Biology (EC 1.14.99). ... Ammonia monooxygenase (EC 1.14.99.39, AMO) is an enzyme, which catalyses the following chemical reaction ammonia + AH2 + O2 ...

https://en.wikipedia.org/wiki/Ammonia_monooxygenase

Musaev, Djamaladdin G.; Basch, Harold; Morokuma, Keiji (2002). "Theoretical Study of the Mechanism of Alkane Hydroxylation and ... "Computational studies of reaction mechanisms of methane monooxygenase and ribonucleotide reductase". Journal of Computational ... 23 (1): 59-76. doi:10.1002/jcc.1157. ISSN 0192-8651. PMID 11913390. S2CID 24420102. Basch, Harold; Ratner, Mark A. (2003). " ...

https://en.wikipedia.org/wiki/Harold_Basch

2-monooxygenase. EC 1.14.15.3: alkane 1-monooxygenase EC 1.14.15.4: steroid 11β-monooxygenase EC 1.14.15.5: corticosterone 18- ... valine N-monooxygenase EC 1.14.14.39: isoleucine N-monooxygenase EC 1.14.14.40: phenylalanine N-monooxygenase EC 1.14.14.41: (E ... steroid 17α-monooxygenase EC 1.14.99.10: Now EC 1.14.14.16, steroid 21-monooxygenase EC 1.14.99.11: estradiol 6β-monooxygenase ... arginine 2-monooxygenase EC 1.13.12.2: lysine 2-monooxygenase EC 1.13.12.3: tryptophan 2-monooxygenase EC 1.13.12.4: lactate 2- ...

https://en.wikipedia.org/wiki/List_of_EC_numbers_(EC_1)

Alkanes are the least reactive class of hydrocarbons due to their apolar sigma bonds. In the absence of high temperatures, high ... but serves as a reactant in the hydroxylation of both aliphatic and aromatic hydrocarbons via monooxygenase and dioxygenase ... It has also been shown that AK-01 uses not only alkanes but also 1-alkenes, 1-alkanols, fatty acids and other organic acids as ... AK-01 is a delta-proteobacterium capable of using C13-C18 alkanes as growth substrates (So et al., 1999). Analysis of labeled ...

https://en.wikipedia.org/wiki/Desulfatibacillum_alkenivorans_AK-01

... (MMO) is an enzyme capable of oxidizing the C-H bond in methane as well as other alkanes. Methane ... The particulate methane monooxygenase and related ammonia monooxygenase are integral membrane proteins, occurring in ... "Evidence that particulate methane monooxygenase and ammonia monooxygenase may be evolutionarily related". FEMS Microbiology ... This is a classic monooxygenase reaction in which two reducing equivalents from NAD(P)H are utilized to split the O-O bond of ...

https://en.wikipedia.org/wiki/Methane_monooxygenase

The transformation can also performed biologically by methane monooxygenase. Overall Transformation RH + H2O + [PtCl6]2− → ROH ... "Reactions of alkanes in solutions of platinum chloride complexes" Zh. Fiz. Khim. 1972, 46, 1353-13544 Gol'dshleger, N. F.; ... and the nucleophilic oxidation of the alkane substrate. An equivalent transformation is performed industrially by steam ... 1] and [2] ). Such premature oxidation shuts down the catalysis. Finally the PtIV-CH2R undergoes nucleophilic attack by OH− or ...

https://en.wikipedia.org/wiki/Shilov_system

These monooxygenases are especially important, as they account for long-chain n-alkane hydroxylation. A. Pacificus is closely ... Found were genes encoding for four integral-membrane alkane monooxygenases, three cytochrome P450 enzymes, and four genes ... Part of this difference results from a 549 nucleotide fragment of the alkane hydroxylase gene alkB, which was amplified from ... Lai Q, Shao Z (December 2012). "Genome sequence of an alkane-degrading bacterium, Alcanivorax pacificus type strain W11-5, ...

https://en.wikipedia.org/wiki/Alcanivorax_pacificus

Alkane hydroxylase is thought to play a similar role in pseudomonas species capable of polyethylene degradation. Once enzymes ... Following the monooxygenase step, the polystyrene molecule is transformed into phenylacetic acid during the upper pathway of ... Bacteria that are capable of degrading this molecule are documented to release monooxygenases to initiate the oxidization of ... 4 (1): 15. doi:10.1186/s40643-017-0145-9. ISSN 2197-4365. S2CID 3698066. Luu, Rita A.; Schneider, Benjamin J.; Ho, Christie C ...

https://en.wikipedia.org/wiki/Plastic_degradation_by_marine_bacteria

Another example is Mycobacterium vaccae, which uses an alkane monooxygenase enzyme to oxidize propane. Accidentally, this ... OX1 can degrade PCE under aerobic conditions by using toluene-o-xylene monooxygenase (ToMO), an enzyme they produce to derive ... Several aerobic microorganisms have been demonstrated to be capable of doing this, including n-alkane, aromatic compound (e.g. ... These bacteria degrade their growth-substrate methane with the enzyme methane monooxygenase (MMO). MMO was discovered to be ...

https://en.wikipedia.org/wiki/Cometabolism

The methanol reacts in the presence of a zeolite catalyst to form alkanes. In terms of mechanism, methanol is partially ... The relevant enzymes are methane monooxygenases, which are found both in soluble and particulate (i.e. membrane-bound) ... alkanes), aromatics, naphthenes (cycloalkanes) and small amounts of olefins (alkenes), mostly from C6 (number of carbon atoms ... Most of the non-condensed gas from the product separator becomes recycled gas and is sent back to the feed stream to Reactor 1 ...

https://en.wikipedia.org/wiki/Gas_to_liquids

The aerobic metabolism of alkanes is carried out through the terminal alkane oxidation pathway, where monooxygenases initiate ... borkumensis can consume a wider variety of alkanes than other known species. A. borkumensis primarily uses alkanes as its ... The A. borkumensis genome has many sequences that each code for a different type of alkane, allowing it to be highly adaptable ... Whereas most organisms use sugars or amino acids for their source of carbon/energy, A. borkumensis uses alkanes, a type of ...

https://en.wikipedia.org/wiki/Alcanivorax_borkumensis

Averaging across all studied species, 98.1%, 48.6%, and 76.4% of the initial Bunker C C10 alkane, C14 alkane, and phenanthrene ... certain fungi possess intracellular networks which constitute the xenome, consisting of cytochrome (CYP) P450 monooxygenases ... The subphylum Saccharomycotina mostly consists of yeasts and includes degraders of n-alkanes, n-alkylbenzenes, crude oil, the ... 198 (Pt 2): 1-11. doi:10.1016/j.jenvman.2017.05.010. PMID 28499155. The levels of adsorption of the phenolic and PAHs were ...

https://en.wikipedia.org/wiki/Mycoremediation

Thermophilic Thermus and Bacillus species have demonstrated higher gene expression for the alkane mono-oxygenase alkB at ... 5 (1): 109-16. doi:10.1111/j.1758-2229.2012.00348.x. PMID 23757139. Krupovic M, Gonnet M, Hania WB, Forterre P, Erauso G (2013 ... 26 (1): 44-71. doi:10.1039/b800164m. PMID 19374122. Rossi M, Ciaramella M, Cannio R, Pisani FM, Moracci M, Bartolucci S (July ... 4 (1): 110-21. Fakayode, S.O. (2005). "Impact assessment of industrial effluent on water quality of the receiving Alaro River ...

https://en.wikipedia.org/wiki/Extremophile

... or methane monooxygenase (MMO), which degrade various environmental pollutants (i.e.: alkanes, alkenes, and mono- and poly- ... encoding a subunit of particulate methane monooxygenase), and fae (encoding formaldehyde activating enzyme) genes." The data ... 1. p. 233-238. Baev M V, Chistoserdova L V, Polanuer B M, et al. "Effect of formaldehyde on growth of obligate methylotroph ... p. 1-10. Marchenko GN, Marchenko ND, Tsygankov YD, Chistoserdov AY. "Organization of threonine biosynthesis genes from the ...

https://en.wikipedia.org/wiki/Methylobacillus_flagellatus

The enzyme methane monooxygenase produces methanol from methane, but cannot be used for industrial-scale reactions. Some ... Etymologically, the word methane is coined from the chemical suffix "-ane", which denotes substances belonging to the alkane ... Hydrogen Cycle Industrial gas Lake Kivu (more general: limnic eruption) List of straight-chain alkanes Methanation Methane ... 57-58 McBride, James Michael (1999) "Development of systematic names for the simple alkanes". Chemistry Department, Yale ...

https://en.wikipedia.org/wiki/Methane

B4.820.464.40 Alkane 1-Monooxygenase D8.811.682.690.708.170.35 D8.244.453.450 D8.811.682.690.708.170.300 D12.776.422.220. ...

https://decs.bvs.br/P/mnchg2015.txt

It is a very reduced product, with a similar amount of electron per carbon atom as alkanes. Alkanes have 6 - 6.3 electrons per ... Odd numbered alkanes For all even numbered alkanes the above reactions completely link them to the main network in CNA. All ... Alkane degradation== To link alkanes to the existing network, the beta-oxidation was chosen as entry point. The reactions from ... For odd numbered alkanes the final reaction however (n = 5), a propionyl-CoA is generated; n-saturated fatty acyl-CoA -> ...

https://2010.igem.org/wiki/index.php?title=Team:TU_Delft/Modeling/MFA/additional_pathways&action=edit&oldid=143902