Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.5.1.4 (deaminase)
5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Strain ZJB-063, a versatile nitrile-amide-degrading strain, was newly isolated from soil in this study. Based on morphology, physiological tests, Biolog and the 16S rDNA sequence, strain ZJB-063 was identified as Bacillus subtilis. ZJB-063 exhibited nitrilase activity without addition of inducers, indicating that the nitrilase in B. subtilis ZJB-063 is constitutive. Interestingly, the strain exhibited nitrile hydratase and amidase activity with the addition of epsilon-caprolactam. Moreover, the substrate spectrum altered with the alteration of enzyme systems due to the addition of epsilon-caprolactam. The constitutive nitrilase was highly specific for arylacetonitriles, while the nitrile hydratase/amidase in B. subtilis ZJB-063 could not only hydrolyze arylacetonitriles but also other nitriles including some aliphatic nitriles and heterocyclic nitriles. Despite comparatively low activity, the amidase of hydratase/amidase system was effective in converting amides to acids. The versatility of this strain in the hydrolysis of various nitriles and amides makes it a potential biocatalyst in organic synthesis.
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PMID:Isolation, identification and characterization of Bacillus subtilis ZJB-063, a versatile nitrile-converting bacterium. 1795 65

In the reductive pyrimidine catabolic pathway uracil and thymine are converted to beta-alanine and beta-aminoisobutyrate. The amidohydrolases of this pathway are responsible for both the ring opening of dihydrouracil and dihydrothymine (dihydropyrimidine amidohydrolase) and the hydrolysis of N-carbamyl-beta-alanine and N-carbamyl-beta-aminoisobutyrate (beta-alanine synthase). The review summarizes what is known about the properties, kinetic parameters, three-dimensional structures and reaction mechanisms of these proteins. The two amidohydrolases of the reductive pyrimidine catabolic pathway have unrelated folds, with dihydropyrimidine amidohydrolase belonging to the amidohydrolase superfamily while the beta-alanine synthase from higher eukaryotes belongs to the nitrilase superfamily. beta-Alanine synthase from Saccharomyces kluyveri is an exception to the rule and belongs to the Acyl/M20 family.
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PMID:Amidohydrolases of the reductive pyrimidine catabolic pathway purification, characterization, structure, reaction mechanisms and enzyme deficiency. 1826 76

The development of green chemistry is traced from the introduction of the concepts of atom economy (atom utilisation) and E factors in the early 1990s. The important role of catalysis in reducing or eliminating waste is emphasised and illustrated with examples from heterogeneous catalytic oxidations with hydrogen peroxide, homogeneous catalytic oxidations and carbonylations and organocatalytic oxidations with stable N-oxy radicals. Catalytic reactions in non-conventional media, e.g. aqueous biphasic, supercritical carbon dioxide and ionic liquids, are presented. Biotransformations involving non-natural reactions of enzymes, e.g. ester ammoniolysis, and the rational design of semi-synthetic enzymes, such as vanadate phytase, are discussed. The optimisation of enzyme properties using in vitro evolution and improvement of their operational stability by immobilisation as cross-linked enzyme aggregates (CLEA) are presented. The ultimate in green chemistry is the integration of catalytic steps into a one-pot, catalytic cascade process. An example of a chemoenzymatic synthesis of an enantiomerically pure amino acid in water and a trienzymatic cascade process using a triple-decker oxynitrilase/nitrilase/amidase CLEA are discussed. Finally, catalytic conversions of renewable raw materials are examined and the biocatalytic aerobic oxidation of starch to carboxy starch is presented as an example of green chemistry in optima forma i.e. a biocompatible product from a renewable raw material using a biocatalytic air oxidation.
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PMID:E factors, green chemistry and catalysis: an odyssey. 1863 90

An enrichment culture from saline soda soils, using acetate as carbon and energy source and 2-phenylpropionitrile as nitrogen source (PPN) at pH 10, resulted in the isolation of strain ANL-alpha CH3. The strain was identified as a representative of the genus Halomonas in the Gammaproteobacteria. The bacterium was capable of PPN utilization as a nitrogen source only, while phenylacetonitrile (PAN) served both as carbon, energy and nitrogen source. This capacity was not described previously for any other haloalkaliphilic bacteria. Apart from the nitriles mentioned above, resting cells of ANL-alpha CH3 also hydrolyzed mandelonitrile, benzonitrile, acrylonitrile, and phenylglycinonitrile, presumably using nitrilase pathway. Neither nitrile hydratase nor amidase activity was detected. The isolate showed a capacity to grow with benzoate and salicylate as carbon and energy source and demonstrated the ability to completely mineralize PAN. These clearly indicated a potential to catabolize aromatic compounds. On the basis of unique phenotype and distinct phylogeny, strain ANL-alpha CH3 is proposed as a novel species of the genus Halomonas--Halomonas nitrilicus sp. nov.
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PMID:Utilization of arylaliphatic nitriles by haloalkaliphilic Halomonas nitrilicus sp. nov. isolated from soda soils. 1879 82

Alcaligenes sp. ECU0401 has been isolated from soil samples with high nitrilase activity against glycolonitrile using the enrichment culture technique. The preferred carbon/nitrogen sources and metal ions were sodium acetate, a composite of peptone and yeast extract, and Cu(2+), respectively. Glycolic acid was obtained in a yield of 96.5% after 14 h of biotransformation from a total of 200 mM glycolonitrile in the mode of sequential addition during the cultivation of Alcaligenes sp. ECU0401 in a 5-L jar fermenter. Fifty micromolars of glycolonitrile could be hydrolyzed in a yield of 94.1% by resting cells after 36 h. The microbial nitrilase system could hydrolyze various nitriles with high activity, and no amidase activity and glycolic acid were observed in hydrolyzing glycolamide. It significantly exhibited high enantioselectivity in the hydrolysis of mandelonitrile and 2-chloromandelonitrile (>99.9% e.e.( p )). Efficient biocatalyst recycling was achieved as a result of immobilization in glutaraldehyde/polyethylenimine cross-linked carrageenan with immobilized cells exhibiting a biocatalyst productivity of 1,042.2 g glycolic acid per gram dry cell weight after 29 batch recycles.
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PMID:Bioproduction of glycolic acid from glycolonitrile with a new bacterial isolate of Alcaligenes sp. ECU0401. 1933 57

Biotransformation of nitriles mediated by nitrile-amide converting enzymes has attracted considerable attention and developed tremendously in the recent years in China since it offers a valuable alternative to traditional chemical reaction which requires harsh conditions. As a result, an upsurge of these promising enzymes (including nitrile hydratase, nitrilase and amidase) has been taking place. This review aims at describing these enzymes in detail. A variety of microorganisms harboring nitrile-amide converting activities have been isolated and identified in China, some of which have already applied with moderate success. Currently, a wide range of high-value compounds such as aliphatic, alicyclic, aromatic and heterocyclic amides and their corresponding acids were provided by these nitrile-amide degrading organisms. Simultaneously, with the increasing demand of chiral substances, the enantioselectivity of the nitrilase superfamily is widely investigated and exploited in China, especially the bioconversion of optically active alpha-substituted phenylacetamides, acids and 2,2-dimethylcyclopropanecarboxamide and 2,2-dimethylcyclopropanecarboxylic acid by means of the catalysts exhibiting excellent stereoselectivity. Besides their synthetic value, the nitrile-amide converting enzymes also play an important role in environmental protection. In this context, cloning of the genes and expression of these enzymes are presented. In the near future in China, an increasing number of novel nitrile-amide converting organisms will be screened and their potential in the synthesis of useful acids and amides will be further exploited.
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PMID:Microbial transformation of nitriles to high-value acids or amides. 1947 77

The operational stabilities of nitrilases from Aspergillus niger K10 and Fusarium solani O1 were examined with 4-cyanopyridine as the substrate in continuous-stirred membrane reactors (CSMRs). The former enzyme was fairly stable at 30 degrees C with a deactivation constant (k (d)) and enzyme half-life of 0.014 h(-1) and 50 h, respectively, but the latter exhibited an even higher stability characterized by k (d) = 0.008 h(-1) and half-life of 87 h at 40 degrees C. Another advantage of this enzyme was its high chemoselectivity, i.e., selective transformation of nitriles into carboxylic acids, while the amide formed a high ratio of A. niger K10 nitrilase product. High conversion rates (>90%) were maintained for about 52 h using the nitrilase from F. solani O1 immobilized in cross-linked enzyme aggregates (CLEAs). The purity of isonicotinic acid was increased from 98% to >99.9% by using two CSMRs connected in series, the first one containing the F. solani O1 nitrilase and the second the amidase from Rhodococcus erythropolis A4 (both enzymes as CLEAs), the amidase hydrolyzing the by-product isonicotinamide.
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PMID:Continuous hydrolysis of 4-cyanopyridine by nitrilases from Fusarium solani O1 and Aspergillus niger K10. 1955 25

The present report identifies the enzymatic substrates of a member of the mammalian nitrilase-like (Nit) family. Nit2, which is widely distributed in nature, has been suggested to be a tumor suppressor protein. The protein was assumed to be an amidase based on sequence homology to other amidases and on the presence of a putative amidase-like active site. This assumption was recently confirmed by the publication of the crystal structure of mouse Nit2. However, the in vivo substrates were not previously identified. Here we report that rat liver Nit2 is omega-amidodicarboxylate amidohydrolase (E.C. 3.5.1.3; abbreviated omega-amidase), a ubiquitously expressed enzyme that catalyzes a variety of amidase, transamidase, esterase and transesterification reactions. The in vivo amidase substrates are alpha-ketoglutaramate and alpha-ketosuccinamate, generated by transamination of glutamine and asparagine, respectively. Glutamine transaminases serve to salvage a number of alpha-keto acids generated through non-specific transamination reactions (particularly those of the essential amino acids). Asparagine transamination appears to be useful in mitochondrial metabolism and in photorespiration. Glutamine transaminases play a particularly important role in transaminating alpha-keto-gamma-methiolbutyrate, a key component of the methionine salvage pathway. Some evidence suggests that excess alpha-ketoglutaramate may be neurotoxic. Moreover, alpha-ketosuccinamate is unstable and is readily converted to a number of hetero-aromatic compounds that may be toxic. Thus, an important role of omega-amidase is to remove potentially toxic intermediates by converting alpha-ketoglutaramate and alpha-ketosuccinamate to biologically useful alpha-ketoglutarate and oxaloacetate, respectively. Despite its importance in nitrogen and sulfur metabolism, the biochemical significance of omega-amidase has been largely overlooked. Our report may provide clues regarding the nature of the biological amidase substrate(s) of Nit1 (another member of the Nit family), which is a well-established tumor suppressor protein), and emphasizes a) the crucial role of Nit2 in nitrogen and sulfur metabolism, and b) the possible link of Nit2 to cancer biology.
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PMID:Identification of the putative tumor suppressor Nit2 as omega-amidase, an enzyme metabolically linked to glutamine and asparagine transamination. 1959 34

Bacterial enzymes capable of nitrile hydrolysis have significant industrial potential. Microbacterium sp. AJ115, Rhodococcus erythropolis AJ270 and AJ300 were isolated from the same location in England and harbour identical nitrile hydratase/amidase gene clusters. Strain AJ270 has been well studied due to its nitrile hydratase and amidase activity. R. erythropolis ITCBP was isolated from Denmark and carries a very similar nitrile hydratase/amidase gene cluster. In this study, an identical nitrilase gene (nit1) was isolated from the four strains, and the nitrilase from strain AJ270 cloned and expressed in Escherichia coli. Analysis of the recombinant nitrilase has shown it to be functional with activity demonstrated towards phenylacetonitrile. A real-time PCR TaqMan assay was developed that allowed nit1 detection directly from soil enrichment cultures without DNA extraction, with nit1 detected in all samples tested. Real-time PCR screening of isolates from these soils resulted in the isolation of nit1 and also very similar nitrilase gene nit2 from a number of Burkholderia sp. The genes nit1 and nit2 have also been detected in many bacteria of different genera but are unstable in these isolates. It is likely that the genes were acquired by horizontal gene transfer and may be wide-spread in the environment.
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PMID:Isolation of identical nitrilase genes from multiple bacterial strains and real-time PCR detection of the genes from soils provides evidence of horizontal gene transfer. 1973 Aug 17

Nitriles are an important type of synthetic intermediates in the production of fine chemicals because of their easy preparations and versatile transformations. The traditional chemical conversion of nitriles to carboxylic acids and amides is feasible but it requires relatively harsh conditions of heat, acid or alkali. Nitrile converting enzymes (nitrilase, nitrile hydratase and amidase) which are used as biocatalyst for the production of fine chemicals have attracted substantial interest because of their ability to convert readily available nitriles into the corresponding higher value amides or acids under mild conditions with excellent chemo-, regio- and stereo-selectivities. Many nitrile converting enzymes have been explored and widely used for the production of fine chemicals. In this paper, various examples of biocatalytic synthesis of pharmaceuticals and their intermediates, agrochemicals and their intermediates, food and feed additives, and other fine chemicals are presented. In the near future, an increasing number of novel nitrile converting enzymes will be screened and their potential in the production of useful fine chemicals will be further exploited.
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PMID:[Applications of nitrile converting enzymes in the production of fine chemicals]. 2035 54


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