Impact of confinement in multimolecular inclusion compounds of melamine and cyanuric acid

Cyanuric acid is shown to be the best supramolecular building block to obtain cage-like clusters. Its triazine ring is also superior to the melamine one for capturing anions as well as cations.

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Molecular Basis of a Bacterial Consortium: Interspecies Catabolism of Atrazine

Applied and Environmental Microbiology ◽

10.1128/aem.64.1.178-184.1998 ◽

1998 ◽

Vol 64 (1) ◽

pp. 178-184 ◽

Cited By ~ 137

Author(s):

Mervyn L. de Souza ◽

David Newcombe ◽

Sam Alvey ◽

David E. Crowley ◽

Anthony Hay ◽

...

Keyword(s):

Nitrogen Source ◽

Southern Hybridization ◽

Cyanuric Acid ◽

Bacterial Species ◽

Bacterial Consortium ◽

Triazine Ring ◽

Carbon And Nitrogen ◽

Consortium Member ◽

Ring Compounds ◽

Pure Cultures

ABSTRACT Pseudomonas sp. strain ADP contains the genes,atzA, -B, and -C, that encode three enzymes which metabolize atrazine to cyanuric acid. Atrazine-catabolizing pure cultures isolated from around the world contain genes homologous to atzA, -B, and -C. The present study was conducted to determine whether the same genes are present in an atrazine-catabolizing bacterial consortium and how the genes and metabolism are subdivided among member species. The consortium contained four or more bacterial species, but two members, Clavibacter michiganese ATZ1 andPseudomonas sp. strain CN1, collectively mineralized atrazine. C. michiganese ATZ1 released chloride from atrazine, produced hydroxyatrazine, and contained a homolog to theatzA gene that encoded atrazine chlorohydrolase. C. michiganese ATZ1 stoichiometrically metabolized hydroxyatrazine to N-ethylammelide and contained genes homologous toatzB and atzC, suggesting that either a functional AtzB or -C catalyzed N-isopropylamine release from hydroxyatrazine. C. michiganese ATZ1 grew on isopropylamine as its sole carbon and nitrogen source, explaining the ability of the consortium to use atrazine as the sole carbon and nitrogen source. A second consortium member, Pseudomonassp. strain CN1, metabolized the N-ethylammelide produced byC. michiganese ATZ1 to transiently form cyanuric acid, a reaction catalyzed by AtzC. A gene homologous to the atzCgene of Pseudomonas sp. strain ADP was present, as demonstrated by Southern hybridization and PCR. Pseudomonassp. strain CN1, but not C. michiganese, metabolized cyanuric acid. The consortium metabolized atrazine faster than didC. michiganese individually. Additionally, the consortium metabolized a much broader set of triazine ring compounds than did previously described pure cultures in which the atzABCgenes had been identified. These data begin to elucidate the genetic and metabolic bases of catabolism by multimember consortia.

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Effect of cyanuric acid amendment on atrazine mineralization in surface soils and detection of the s-triazine ring-cleavage gene trzD

Soil Biology and Biochemistry ◽

10.1016/s0038-0717(01)00072-4 ◽

2001 ◽

Vol 33 (11) ◽

pp. 1539-1545 ◽

Cited By ~ 8

Author(s):

Ellen B. Ostrofsky ◽

Jayne B. Robinson ◽

Samuel J. Traina ◽

Olli H. Tuovinen

Keyword(s):

Cyanuric Acid ◽

Ring Cleavage ◽

Triazine Ring ◽

Surface Soils

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Arthrobacter aurescens TC1 Metabolizes Diverse s-Triazine Ring Compounds

Applied and Environmental Microbiology ◽

10.1128/aem.68.12.5973-5980.2002 ◽

2002 ◽

Vol 68 (12) ◽

pp. 5973-5980 ◽

Cited By ~ 139

Author(s):

Lisa C. Strong ◽

Charlotte Rosendahl ◽

Gilbert Johnson ◽

Michael J. Sadowsky ◽

Lawrence P. Wackett

Keyword(s):

Cyanuric Acid ◽

Sole Source ◽

Triazine Ring ◽

High Sequence Identity ◽

Substrate Analogs ◽

Ring Compounds ◽

Arthrobacter Aurescens ◽

Growth Substrates ◽

Energy Consuming ◽

Cyano Groups

ABSTRACT Arthrobacter aurescens strain TC1 was isolated without enrichment by plating atrazine-contaminated soil directly onto atrazine-clearing plates. A. aurescens TC1 grew in liquid medium with atrazine as the sole source of nitrogen, carbon, and energy, consuming up to 3,000 mg of atrazine per liter. A. aurescens TC1 is metabolically diverse and grew on a wider range of s-triazine compounds than any bacterium previously characterized. The 23 s-triazine substrates serving as the sole nitrogen source included the herbicides ametryn, atratone, cyanazine, prometryn, and simazine. Moreover, atrazine substrate analogs containing fluorine, mercaptan, and cyano groups in place of the chlorine substituent were also growth substrates. Analogs containing hydrogen, azido, and amino functionalities in place of chlorine were not growth substrates. A. aurescens TC1 also metabolized compounds containing chlorine plus N-ethyl, N-propyl, N-butyl, N-s-butyl, N-isobutyl, or N-t-butyl substituents on the s-triazine ring. Atrazine was metabolized to alkylamines and cyanuric acid, the latter accumulating stoichiometrically. Ethylamine and isopropylamine each served as the source of carbon and nitrogen for growth. PCR experiments identified genes with high sequence identity to atzB and atzC, but not to atzA, from Pseudomonas sp. strain ADP.

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Gene Sequence and Properties of ans-Triazine Ring-Cleavage Enzyme from Pseudomonassp. Strain NRRLB-12227

Applied and Environmental Microbiology ◽

10.1128/aem.65.8.3512-3517.1999 ◽

1999 ◽

Vol 65 (8) ◽

pp. 3512-3517 ◽

Cited By ~ 61

Author(s):

Jeffrey S. Karns

Keyword(s):

High Performance ◽

Cyanuric Acid ◽

Nitrogen Sources ◽

Complete Removal ◽

Competitive Inhibitor ◽

Ring Structure ◽

Ring Cleavage ◽

Triazine Ring ◽

Cloned Gene ◽

Acid Amidohydrolase

ABSTRACT Pesticides based on the s-triazine ring structure are widely used in cultivation of food crops. Cleavage of thes-triazine ring is an important step in the mineralization of s-triazine compounds and hence in their complete removal from the environment. Cyanuric acid amidohydrolase cleaves cyanuric acid (2,4,6-trihydroxy-s-triazine), which yields carbon dioxide and biuret; the biuret is subject to further metabolism, which yields CO2 and ammonia. The trzD gene encoding cyanuric acid amidohydrolase was cloned into pMMB277 fromPseudomonas sp. strain NRRLB-12227, a strain that is capable of utilizing s-triazines as nitrogen sources. Hydrolysis of cyanuric acid was detected in crude extracts ofEscherichia coli containing the cloned gene by monitoring the disappearance of cyanuric acid and the appearance of biuret by high-performance liquid chromatography (HPLC). DEAE and hydrophobic interaction HPLC were used to purify cyanuric acid amidohydrolase to homogeneity, and a spectrophotometric assay for the purified enzyme was developed. The purified enzyme had an apparentKm of 0.05 mM for cyanuric acid at pH 8.0. The enzyme did not cleave any other s-triazine or hydroxypyrimidine compound, although barbituric acid (2,4,6-trihydroxypyrimidine) was found to be a strong competitive inhibitor. Neither the nucleotide sequence of trzD nor the amino acid sequence of the gene product exhibited a significant level of similarity to any known gene or protein.

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Effect of S-triazine Ring Substitution on the Synthesis of Organic Resorcinol-Formaldehyde Xerogels

Gels ◽

10.3390/gels6030021 ◽

2020 ◽

Vol 6 (3) ◽

pp. 21

Author(s):

Martin Prostredný ◽

Caio Ledingham ◽

Ivan A. Principe ◽

Abdelkarim S. M. Altoumi ◽

Ashleigh J. Fletcher

Keyword(s):

Cyanuric Acid ◽

Cross Linking ◽

Gel Formation ◽

Triazine Ring ◽

Intermediate Species ◽

Acid Base ◽

Resorcinol Formaldehyde ◽

Rf Systems ◽

Low Concentrations ◽

High Concentrations

Resorcinol (R) and formaldehyde (F) gel synthesis has been well-studied along with alternative reagents. We present the synthesis of formaldehyde-based xerogels using chemically similar s-triazine precursors, with comparison to traditional analogues. The substitution ranges from tri-hydroxyl to tri-amine, with an intermediate species, allowing changing chemistry to be investigated. Each molecule (X) offers different acid/base properties, known to influence gel formation, as well as differences in crosslinking potential. Varying X/F ratios were selected to recreate the stoichiometry used in RF systems, where one represented higher F to match the increased reaction sites of the additives. X/C ratios were selected to probe different catalyst (C) ratios, while working within the range likely to produce viable gels. Results obtained show little impact for ammeline as an additive due to its similarity to resorcinol (activation sites and pKa); while melamine and cyanuric acid show differing behavior depending on the level of addition. Low concentrations show melamine to have the most impact due to increased activation and competition for formaldehyde; while at high concentrations, cyanuric acid is shown to have the greatest impact as it creates a more acidic environment, which diminishes textural character, possibly attributable to larger clusters and/or weaker cross-linking of the system.

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Mechanism of degradation of a nitrogenous heterocycle induced by a reductive radical: decomposition of a sym-triazine ring

Physical Chemistry Chemical Physics ◽

10.1039/c7cp00004a ◽

2017 ◽

Vol 19 (14) ◽

pp. 9354-9357 ◽

Cited By ~ 4

Author(s):

Gengxin Lyu ◽

Guosheng Shi ◽

Liang Tang ◽

Haiping Fang ◽

Minghong Wu

Keyword(s):

Water Treatment ◽

Natural Environment ◽

Cyanuric Acid ◽

Triazine Ring ◽

Degradation Processes ◽

Radical Decomposition ◽

Mechanism Of Degradation ◽

Nitrogenous Heterocycle ◽

Important Intermediate

Cyanuric acid, a major component of many materials and chemicals, and also the most important intermediate in the degradation processes of sym-triazine compounds in the natural environment, as well as being used for water treatment, was selected to elucidate the mechanism of degradation of nitrogenous materials.

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