salicylates and catechol

The pollution of aquatic environments by drugs is a problem for which scarce research has been conducted in regards of their removal. Amycolatopsis sp. Poz 14 presents the ability to biotransformation naphthalene at high efficiency, therefore, in this work this bacterium was proposed as an assimilator of naproxen and carbamazepine. Growth curves at different concentrations of naproxen and carbamazepine showed that Amycolatopsis sp. Poz 14 is able to utilize these drugs at a concentration of 50 mg L

Topics: Actinomycetales; Biodegradation, Environmental; Biotransformation; Carbamazepine; Carbon; Catechol 1,2-Dioxygenase; Catechols; Dioxygenases; Environmental Pollution; Gentisates; Hydroxybenzoate Ethers; Kinetics; Metabolic Networks and Pathways; Mixed Function Oxygenases; Naphthalenes; Naproxen; Salicylates

Phenol- and naphthalene-degrading indigenous Pseudomonas pseudoalcaligenes strain C70 has great potential for the bioremediation of polluted areas. It harbours two chromosomally located catechol meta pathways, one of which is structurally and phylogenetically very similar to the Pseudomonas sp. CF600 dmp operon and the other to the P. stutzeri AN10 nah lower operon. The key enzymes of the catechol meta pathway, catechol 2,3-dioxygenase (C23O) from strain C70, PheB and NahH, have an amino acid identity of 85%. The metabolic and regulatory phenotypes of the wild-type and the mutant strain C70ΔpheB lacking pheB were evaluated. qRT-PCR data showed that in C70, the expression of pheB- and nahH-encoded C23O was induced by phenol and salicylate, respectively. We demonstrate that strain C70 is more effective in the degradation of phenol and salicylate, especially at higher substrate concentrations, when these compounds are present as a mixture; i.e., when both pathways are expressed. Moreover, NahH is able to substitute for the deleted PheB in phenol degradation when salicylate is also present in the growth medium. The appearance of a yellow intermediate 2-hydroxymuconic semialdehyde was followed by the accumulation of catechol in salicylate-containing growth medium, and lower expression levels and specific activities of the C23O of the sal operon were detected. However, the excretion of the toxic intermediate catechol to the growth medium was avoided when the growth medium was supplemented with phenol, seemingly due to the contribution of the second meta pathway encoded by the phe genes.

Topics: Bacterial Proteins; Base Sequence; Biodegradation, Environmental; Catechol 2,3-Dioxygenase; Catechols; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Phenol; Promoter Regions, Genetic; Pseudomonas pseudoalcaligenes; Salicylates; Substrate Specificity

Aspergilli play major roles in the natural turnover of elements, especially through the decomposition of plant litter, but the end catabolism of lignin aromatic hydrocarbons remains largely unresolved. The 3-oxoadipate pathway of their degradation combines the catechol and the protocatechuate branches, each using a set of specific genes. However, annotation for most of these genes is lacking or attributed to poorly- or un-characterised families. Aspergillus nidulans can utilise as sole carbon/energy source either benzoate or salicylate (upstream aromatic metabolites of the protocatechuate and the catechol branches, respectively). Using this cultivation strategy and combined analyses of comparative proteomics, gene mining, gene expression and characterisation of particular gene-replacement mutants, we precisely assigned most of the steps of the 3-oxoadipate pathway to specific genes in this fungus. Our findings disclose the genetically encoded potential of saprophytic Ascomycota fungi to utilise this pathway and provide means to untie associated regulatory networks, which are vital to heightening their ecological significance.

Topics: Adipates; Aspergillus nidulans; Benzoic Acid; Catechols; Enzymes; Gene Knock-In Techniques; Genes, Fungal; Hydroxybenzoates; Lignin; Metabolic Networks and Pathways; Proteomics; Salicylates

The ability of Pseudomonas fluorescens 26K strain to utilize naphthalene at concentrations up to 600 mg/liter as the sole source of carbon and energy in mineral liquid media was shown. Using HPLC, TLC, and mass-spectrometry, the intermediates of naphthalene transformation by this strain were identified as naphthalene cis-1,2-dihydrodiol, salicylaldehyde, salicylate, catechol, 2-hydroxymuconic semialdehyde, and 1-naphthol. Catechol 2,3-dioxygenase (a homotetramer with native molecular mass 125 kDa) and NAD+-dependent homohexameric naphthalene cis-1,2-dihydrodiol dehydrogenase with native molecular mass 160 kDa were purified from crude extract of the strain and characterized. NAD+-dependent homodimeric salicylaldehyde dehydrogenase with molecular mass 110 kDa was purified and characterized for the first time. Based on the data, a pathway of naphthalene degradation by P. fluorescens 26K is suggested.

Topics: Aldehyde Oxidoreductases; Aldehydes; Catechol 2,3-Dioxygenase; Catechols; Chromatography, High Pressure Liquid; Electrophoresis, Polyacrylamide Gel; Fatty Acids, Unsaturated; Mass Spectrometry; Naphthalenes; Naphthols; Oxidoreductases Acting on CH-CH Group Donors; Pseudomonas fluorescens; Salicylates

The polyphenol oxidase (LsPPO) from a wild edible mushroom Lactarius salmonicolor was purified using a Sepharose 4B-L-tyrosine-p-amino benzoic acid affinity column. At the optimum pH and temperature, the K(M) and V(Max) values of LsPPO towards catechol, 4-methylcatechol and pyrogallol were determined as 0.025 M & 0.748 EU/mL, 1.809 x 10(- 3) M & 0.723 EU/mL and 9.465 x 10(- 3) M & 0.722 EU/mL, respectively. Optimum pH and temperature values of LsPPO for the three substrates above ranged between the pH 4.5-11.0 and 5-50 degrees C. Enzyme activity decreased due to heat denaturation with increasing temperature. Effects of a variety of classical PPO inhibitors were investigated opon the activity of LsPPO using catechol as the substrate. IC(50) values for glutathione, p-aminobenzenesulfonamide, L-cysteine, L-tyrosine, oxalic acid, beta-mercaptoethanol and syringic acid were determined as 9.1 x 10(- 4), 2.3 x 10(- 4) M, 1.5 x 10(- 4) M, 3.8 x 10(- 7) M, 1.2 x 10(- 4) M, 4.9 x 10(- 4) M, and 4 x 10(- 4) M respectively. Thus L-tyrosine was by far the most effective inhibitor. Interestingly, sulfosalicylic acid behaved as an activator of LsPPO in this study.

Topics: Agaricales; Benzenesulfonates; Catechol Oxidase; Catechols; Enzyme Inhibitors; Hydrogen-Ion Concentration; Kinetics; Pyrogallol; Salicylates; Substrate Specificity; Temperature; Tyrosine

Acridone alkaloids formed by acridone synthase in Ruta graveolens L. are composed of N-methylanthraniloyl CoA and malonyl CoAs. A 1095 bp cDNA from elicited Ruta cells was expressed in Escherichia coli, and shown to encode S-adenosyl-l-methionine-dependent anthranilate N-methyltransferase. SDS-PAGE of the purified enzyme revealed a mass of 40 +/- 2 kDa, corresponding to 40 059 Da for the translated polypeptide, whereas the catalytic activity was assigned to a homodimer. Alignments revealed closest relationships to catechol or caffeate O-methyltransferases at 56% and 55% identity (73% similarity), respectively, with little similarity ( approximately 20%) to N-methyltransferases for purines, putrescine, glycine, or nicotinic acid substrates. Notably, a single Asn residue replacing Glu that is conserved in caffeate O-methyltransferases determines the catalytic efficiency. The recombinant enzyme showed narrow specificity for anthranilate, and did not methylate catechol, salicylate, caffeate, or 3- and 4-aminobenzoate. Moreover, anthraniloyl CoA was not accepted. As Ruta graveolens acridone synthase also does not accept anthraniloyl CoA as a starter substrate, the anthranilate N-methylation prior to CoA activation is a key step in acridone alkaloid formation, channelling anthranilate from primary into secondary branch pathways, and holds promise for biotechnological applications. RT-PCR amplifications and Western blotting revealed expression of the N-methyltransferase in all organs of Ruta plants, particularly in the flower and root, mainly associated with vascular tissues. This expression correlated with the pattern reported previously for expression of acridone synthase and acridone alkaloid accumulation.

Topics: 4-Aminobenzoic Acid; Acridines; Acridones; Amino Acid Sequence; Blotting, Western; Catechols; Methyltransferases; Molecular Sequence Data; Molecular Structure; ortho-Aminobenzoates; Plant Proteins; Polymerase Chain Reaction; Recombinant Proteins; Reverse Transcriptase Polymerase Chain Reaction; Rutaceae; Salicylates; Substrate Specificity

Metabolic profiling was used to investigate the molecular phenotypes of a transgenic Populus tremula x P. alba hybrid expressing the nahG transgene, a bacterial gene encoding salicylate hydroxylase that converts salicylic acid to catechol. Despite the efficacy of this transgenic approach to reduce salicylic acid levels in other model systems and thereby elucidate roles for salicylic acid in plant signaling, transgenic poplars had similar foliar levels of salicylic acid and catechol to that of non-transformed controls and exhibited no morphological phenotypes. To gain a deeper understanding of the basis for these observations, we analyzed metabolic profiles of leaves as influenced by transgene expression. Expression of nahG decreased quinic acid conjugates and increased catechol glucoside, while exerting little effect on levels of salicylic acid and catechol, the substrate and product, respectively, of the nahG enzyme. This suggests a biological role of elevated constitutive salicylic acid levels in Populus, in contrast to other plant systems in which nahG dramatically reduces salicylic acid levels.

Topics: Bacterial Proteins; Blotting, Northern; Catechols; Mixed Function Oxygenases; Plants, Genetically Modified; Populus; RNA, Plant; Salicylates; Transgenes

Nitrate-dependent salicylate degradation by the denitrifying Pseudomonas butanovora was investigated and the molar ratio of the cometabolism under anaerobic circumstances was determined. The bacterium was able to utilize salicylate as an electron donor for the reduction of nitrate. Salicylate was eliminated via catechol, which is degraded by means of catechol 2,3-oxygenases (meta-cleavage), forming 2-hydroxymuconic semialdehyde. The molar ratios of NO(3)(-)-N:salicylate existing during the experiment accorded well with the assumed 1:1 molar ratio. The tolerances of the growth, the salicylate degradation and the denitrification of P. butanovora to various heavy metal ions were also studied. Although the strain was tolerant to Pb(2+) and Cu(2+) up to 1 mM in complete medium, salicylate utilization took place only up to a concentration of 0.1 mM for both heavy metal ions. Of the heavy metal ions investigated, Cd(2+) (at a concentration of 0.05 mM) displayed the highest inhibitory effect on salicylate degradation by P. butanovora.

Topics: Anaerobiosis; Catechols; Cell Proliferation; Industrial Microbiology; Metals, Heavy; Nitrates; Oxygenases; Pseudomonas; Salicylates

A 5-kbp region upstream of the are-ben-cat genes was cloned from Acinetobacter sp. strain ADP1, extending the supraoperonic cluster of catabolic genes to 30 kbp. Four open reading frames, salA, salR, salE, and salD, were identified from the nucleotide sequence. Reverse transcription-PCR studies suggested that these open reading frames are organized into two convergent transcription units, salAR and salDE. The salE gene, encoding a protein of 239 residues, was ligated into expression vector pET5a. Its product, SalE, was shown to have esterase activity against short-chain alkyl esters of 4-nitrophenol but was also able to hydrolyze ethyl salicylate to ethanol and salicylic acid. A mutant of ADP1 with a Km(r) cassette introduced into salE had lost the ability to utilize only ethyl and methyl salicylates of the esters tested as sole carbon sources, and no esterase activity against ethyl salicylate could be detected in cell extracts. SalE was induced during growth on ethyl salicylate but not during growth on salicylate itself. salD encoded a protein of undetermined function with homologies to the Escherichia coli FadL membrane protein, which is involved in facilitating fatty acid transport, and a number of other proteins detected during aromatic catabolism, which may also function in hydrocarbon transport or uptake processes. A Km(r) cassette insertion in salD deleteriously affected cell growth and viability. The salA and salR gene products closely resemble two Pseudomonas proteins, NahG and NahR, respectively encoding salicylate hydroxylase and the LysR family regulator of both salicylate and naphthalene catabolism. salA was cloned into pUC18 together with salR and salE, and its gene product showed salicylate-inducible hydroxylase activity against a range of substituted salicylates, with the same relative specific activities as found in wild-type ADP1 grown on salicylate. Mutations involving insertion of Km(r) cassettes into salA and salR eliminated expression of salicylate hydroxylase activity and the ability to grow on either salicylate or ethyl salicylate. Studies of mutants with disruptions of genes of the beta-ketoadipate pathway with or without an additional salE mutation confirmed that ethyl salicylate and salicylate were channeled into the beta-ketoadipate pathway at the level of catechol and thence dissimilated by the cat gene products. SalR appeared to regulate expression of salA but not salE.

Topics: Acinetobacter; Bacterial Proteins; Catechols; Cloning, Molecular; Esterases; Esters; Gene Expression Regulation, Bacterial; Genes, Bacterial; Kinetics; Mixed Function Oxygenases; Molecular Sequence Data; Multigene Family; Mutagenesis, Insertional; Operon; Phenotype; Recombinant Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Bacterial; Salicylates; Sequence Homology, Amino Acid; Substrate Specificity

The healing-promotion property of saliva has been observed in the past, but its underlying mechanism has never been elucidated. We hypothesized a mechanism based on salivary proteins binding to redox active metal ions, rendering them nonactive in their capacity for free radical production.. Examination of this mechanism was conducted by comparing the redox activity of protein-rich saliva with protein-poor saliva. We also examined the redox activity mediated by these 2 kinds of saliva following the in vitro addition of iron, copper, and manganese. Saliva samples were analyzed for their redox activity by measuring the ascorbate-driven and saliva (diluted 1:2)-mediated conversion of salicylate to its 2,3- and 2.5-dihydroxybenzoates and catechol metabolites.. The concentrations of salicylate metabolites formed by protein-rich saliva were significantly lower by 45% (P < .05), 66% (P < .01), and 54% (P < .05), respectively, when compared with those formed by protein-poor saliva. The capacity of saliva in suppressing redox activity was found to be inversely related to the concentrations of iron and copper added (but not manganese), but correlated well with the protein content. When the highest concentrations of iron (15 mumol/L) and copper (10 mumol/L) were added to protein-rich saliva, the concentrations of salicylate metabolites produced were only 0.3% to 1% of those of non-saliva-containing controls (P < .01). However, when these concentrations of iron and copper were added to protein-poor saliva, significantly higher values of redox activity were detected, and the concentrations of the salicylate derivatives produced were 2.1% to 8.1% of those of non-saliva-containing controls (P < .01). In contrast, when the lowest concentrations of iron (2 mumol/L) and copper (0.1 mumol/L) were added, 2.8 to 4 times lower concentrations of salicylate derivatives were produced (P < .01).. These results substantiate our hypothesis that saliva has a profound capacity for reducing redox activity rendered by transition metal ions, correlating well with its protein content.

Topics: Ancitabine; Animals; Antimetabolites, Antineoplastic; Antioxidants; Ascorbic Acid; Catechols; Copper; Free Radicals; Gentisates; Hydroxybenzoates; Iron; Iron Chelating Agents; Male; Manganese; Metals; Oxidation-Reduction; Parasympathomimetics; Parotid Gland; Pilocarpine; Protein Binding; Rats; Rats, Wistar; Salicylates; Saliva; Salivary Proteins and Peptides; Wound Healing

The roles of salicylic acid (SA) and H2O2 in the induction of PR proteins in tobacco have been examined. Studies were conducted on wild-type tobacco and plants engineered to express a bacterial salicylate hydroxylase capable of metabolizing SA to catechol (SH-L plants). Wild-type and PR-1a-GUS-transformed plants express PR-1a following challenge with Pseudomonas syringae pathovar syringae, SA or 2,6-dichloro-isonicotinic acid (INA). In contrast, SH-L plants failed to respond to SA but did express PR-1a following INA treatment. H2O2 and the irreversible catalase inhibitor 3-amino-1,2,4-triazole (3-AT) were found to be weak inducers of PR-1a expression (relative to SA) in wild-type tobacco but were unable to induce PR-1a in SH-L plants, suggesting that the action of these compounds depends upon the accumulation of SA. A model has been proposed suggesting that SA binds to and inhibits a catalase inducing an increase in H2O2 leading to PR protein expression. Catalase activity has been measured in tobacco and no significant changes in activity following infection with P. syringae pv. syringae were detected. Furthermore, inhibition of catalase activity in vitro in plant extracts requires pre-incubation and only occurs at SA concentrations above 250 microM. Leaf disks preincubated with 1 mM SA do accumulate SA to these levels and PR-1a is efficiently induced but there is no apparent inhibition of catalase activity. It is also shown that a SA-responsive gene, PR-1a, and a H2O2-sensitive gene, AoPR-1, are both relatively insensitive to 3-AT suggesting that induction of these genes is unlikely to be due entirely to inhibition of an endogenous catalase.

Topics: Amitrole; Base Sequence; Biological Transport; Catalase; Catechols; Gene Expression Regulation, Plant; Genes, Reporter; Glucuronidase; Hydrogen Peroxide; Isonicotinic Acids; Mixed Function Oxygenases; Molecular Sequence Data; Nicotiana; Plant Proteins; Plants, Genetically Modified; Plants, Toxic; Pseudomonas; Salicylates; Salicylic Acid; Signal Transduction

Transgenic tobacco (Nicotiana tabacum L.) plants carrying a fusion between the nopaline synthase (nos) promoter and chloramphenicol acetyltransferase (CAT) reporter gene (caf) were tested for their response to treatment with H2O2. The nos promoter-driven CAT activity increased significantly by addition of H2O2, reaching the maximum level at 15 mM. Kinetic analysis for CAT activity showed that induction by H2O2 was similar to that of methyl jasmonate (MJ), but was much slower than induction by salicylic acid (SA). Time-course experiments for mRNA level also revealed that the response to H2O2 treatment was similar to that of MJ. The nos promoter displayed a rapid and transient induction of mRNA with SA treatment, with the maximum levels occurring at 3 h, whereas the levels induced by H2O2 or MJ treatment increased continuously during the 11-h experimental period. The antioxidants N-acetyl-L-cysteine and catechol did not alter the SA effect. The responses of the nos promoter to H2O2, MJ, and wounding were significantly reduced by deletions of the CAAT box region and the sequence between -112 and -101. However, these deletions did not significantly alter the SA response. This suggests that H2O2 may have a different mechanism from that of SA for inducing nos promotor activity.

Topics: Acetylcysteine; Amino Acid Oxidoreductases; Antioxidants; Catechols; Chloramphenicol O-Acetyltransferase; Hydrogen Peroxide; Kinetics; Nicotiana; Plants, Genetically Modified; Plants, Toxic; Promoter Regions, Genetic; RNA, Messenger; Salicylates; Salicylic Acid

To provide more experimental evidence for the proposed role of oxygen free radicals in red blood cell (RBC) damage in beta-thalassemia, hydroxyl radical generation was studied in thalassemic (Th) vs. normal (N) RBC. .OH fluxes were quantified by the conversion of salicylic acid (SA) into its hydroxylated products, 2,3- and 2,5-dihydroxybenzoic acids (DHBA) and catechol, assayed with HPLC coupled to electrochemical detection. No significant difference in spontaneous .OH generation between N-RBC and Th-RBC was found. Ascorbic acid (0.5-3.0 mM) induced many-fold increases in SA hydroxylation in a dose-dependent manner in both types of cells. In the presence of ascorbate (1.0 mM), the SA hydroxylated products were determined in Th-RBC vs. N-RBC as follows (nmol/ml): 2,5-DHBA, 1.45 +/- 0.06 vs. 1.81 +/- 0.05 (p = 0.001); 2,3-DHBA, 1.89 +/- 0.21 vs. 1.15 +/- 0.08 (p = 0.008) and catechol, 0.87 +/- 0.13 vs. 0.38 +/- 0.05 (p = 0.006). The results showed significant increase in the total SA hydroxylation in Th-RBC as compared to N-RBC with a tendency to form 2,3-DHBA and catechol at the expanse of 2,5-DHBA. The excessive .OH generation in Th-RBC is attributed to the abnormally high content of redox active iron in the cytosolic and/or membrane compartments of these cells.

Topics: beta-Thalassemia; Catechols; Erythrocytes; Gentisates; Humans; Hydroxybenzoates; Hydroxyl Radical; In Vitro Techniques; Iron; Oxidation-Reduction; Salicylates; Salicylic Acid

Cells of Pseudomonas sp. strain HBP1 grown on 2-hydroxy- or 2,2'-dihydroxybiphenyl contain NADH-dependent monooxygenase activity that hydroxylates 2,2'-dihydroxybiphenyl. The product of this reaction was identified as 2,2',3-trihydroxybiphenyl by 1H nuclear magnetic resonance and mass spectrometry. Furthermore, the monooxygenase activity also hydroxylates 2,2',3-trihydroxybiphenyl at the C-3' position, yielding 2,2',3,3'-tetrahydroxybiphenyl as a product. An estradiol ring cleavage dioxygenase activity that acts on both 2,2',3-tri- and 2,2',3,3'-tetrahydroxybiphenyl was partially purified. Both substrates yielded yellow meta-cleavage compounds that were identified as 2-hydroxy-6-(2-hydroxyphenyl)-6-oxo-2,4-hexadienoic acid and 2-hydroxy-6-(2,3-dihydroxyphenyl)-6-oxo-2,4-hexadienoic acid, respectively, by gas chromatography-mass spectrometry analysis of their respective trimethylsilyl derivatives. The meta-cleavage products were not stable in aqueous incubation mixtures but gave rise to their cyclization products, 3-(chroman-4-on-2-yl)pyruvate and 3-(8-hydroxychroman-4-on-2-yl)pyruvate, respectively. In contrast to the meta-cleavage compounds, which were turned over to salicylic acid and 2,3-dihydroxybenzoic acid, the cyclization products are not substrates to the meta-cleavage product hydrolase activity. NADH-dependent salicylate monooxygenase activity catalyzed the conversions of salicylic acid and 2,3-dihydroxybenzoic acid to catechol and pyrogallol, respectively. The partially purified estradiol ring cleavage dioxygenase activity that acted on the hydroxybiphenyls also produced 2-hydroxymuconic semialdehyde and 2-hydroxymuconic acid from catechol and pyrogallol, respectively.

Topics: Biphenyl Compounds; Catechols; Fatty Acids, Unsaturated; Hydroxybenzoates; Kinetics; Magnetic Resonance Spectroscopy; Mass Spectrometry; Mixed Function Oxygenases; Molecular Structure; Phenols; Pseudomonas; Pyrogallol; Salicylates; Spectrophotometry, Ultraviolet; Substrate Specificity

Topics: Catechols; Enzyme Inhibitors; Flavin-Adenine Dinucleotide; Hydroxylation; Mixed Function Oxygenases; NAD; Oxygen Isotopes; Research; Salicylates; Sulfonic Acids

Topics: Acetates; Azotobacter; Azotobacter vinelandii; Benzoates; Catechols; Chromatography; Citrates; Fumarates; Malates; Mannitol; Manometry; Metabolism; Pyruvates; Research; Salicylates; Succinates

Topics: Catechols; Hydroxybenzoates; Phenols; Salicylates; Salicylic Acid

Topics: Arthritis; Arthritis, Rheumatoid; Catechols; Humans; Rheumatic Fever; Salicylates; Sodium