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Biocatalysis for Biobased Chemicals  [PDF]
Rubén de Regil,Georgina Sandoval
Biomolecules , 2013, DOI: 10.3390/biom3040812
Abstract: The design and development of greener processes that are safe and friendly is an irreversible trend that is driven by sustainable and economic issues. The use of Biocatalysis as part of a manufacturing process fits well in this trend as enzymes are themselves biodegradable, require mild conditions to work and are highly specific and well suited to carry out complex reactions in a simple way. The growth of computational capabilities in the last decades has allowed Biocatalysis to develop sophisticated tools to understand better enzymatic phenomena and to have the power to control not only process conditions but also the enzyme’s own nature. Nowadays, Biocatalysis is behind some important products in the pharmaceutical, cosmetic, food and bulk chemicals industry. In this review we want to present some of the most representative examples of industrial chemicals produced in vitro through enzymatic catalysis.
Whey upgrading by enzyme biocatalysis
Electronic Journal of Biotechnology , 2011,
Abstract: whey is a co-product of processes for the production of cheese and casein that retains most of the lactose content in milk. world production of whey is estimated around 200 million tons per year with an increase rate of about 2%/per year. milk production is seasonal, so surplus whey is unavoidable. traditionally, whey producers have considered it as a nuisance and strategies of whey handling have been mostly oriented to their more convenient disposal. this vision has been steadily evolving because of the upgrading potential of whey major components (lactose and whey proteins), but also because of more stringent regulations of waste disposal. only the big cheese manufacturing companies are in the position of implementing technologies for their recovery and upgrading, so there is a major challenge in incorporating medium and small size producers to a platform of whey utilization, conciliating industrial interest with environmental protection within the framework of sustainable development. within this context, among the many technological options for whey upgrading, transformation of whey components by enzyme biocatalysis appears as prominent. in fact, enzymes are green catalysts that can perform a myriad of transformation reactions under mild conditions and with strict specificity, so reducing production costs and environmental burden. this review pretends to highlight the impact of biocatalysis within a platform of whey upgrading. technological options are shortly reviewed and then an in-depth and critical appraisal of enzyme technologies for whey upgrading is presented, with a special focus on newly developed enzymatic processes of organic synthesis, where the added value is high, being then a powerful driving force for industrial implementation.
Screening and Improving the Recombinant Nitrilases and Application in Biotransformation of Iminodiacetonitrile to Iminodiacetic Acid  [PDF]
Zhi-Qiang Liu, Peter James Baker, Feng Cheng, Ya-Ping Xue, Yu-Guo Zheng, Yin-Chu Shen
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0067197
Abstract: In this study, several nitrilase genes from phylogenetically distinct organisms were expressed and purified in E. coli in order to study their ability to mediate the biotransformation of nitriles. We identified three nitrilases: Acidovorax facilis nitrilase (AcN); Alcaligenes fecalis nitrilase (AkN); and Rhodococcus rhodochrous nitrilase (RkN), which catalyzed iminodiacetonitrile (IDAN) to iminodiacetic acid (IDA). AcN demonstrated 8.8-fold higher activity for IDAN degradation as compared to AkN and RkN. Based on homology modeling and previously described ‘hot spot’ mutations, several AcN mutants were screened for improved activity. One mutant M3 (F168V/L201N/S192F) was identified, which demonstrates a 41% enhancement in the conversion as well as a 2.4-fold higher catalytic efficiency towards IDAN as compared to wild-type AcN.
Study on nitrile-degrading microorganisms
Li Wenzhong,Zhang Hongyi,Yang HuifangInstitute of Microbiology,Academia Sinica,Beijing,China,
Li Wenzhong
,Zhang Hongyi,Yang Huifang

环境科学学报(英文版) , 1991,
Abstract: Two strains of bacteria were isolated from nitrile polluted soils, and identified as Corynebacterium boffmanii and Arthrobacter flavescens. Acetonitrile, propionitrile, butyronitrile and acrylonitrile were degraded by these bacteria to yield corresponding amides, carboxylic acids and ammonia. The nitrile-degrading abilities of these strains were investigated. The removal rates for the nitrile were nearly 100%, after these bacteria were grown in medium containing 10000 ppm of aceto-, propio-, or butyronitrile at 28 ℃ for 24h. When the reaction mkture consisting of 5000 ppm of above mentioned nitriles or acrylonitrile and 20g (dry cell) /L resting cells of the two strains in 0.06mol/L phosphate buffer (pH7.5) was incubated separately at 25 ℃ with moderate shaking for 15 or 45 min, the nitrile could be degraded completely. The optimum growth conditions for C.hoffmanii and A.flavescens were studied as well.
Nitrile Hydratase Genes Are Present in Multiple Eukaryotic Supergroups  [PDF]
Alan O. Marron, Michael Akam, Giselle Walker
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0032867
Abstract: Background Nitrile hydratases are enzymes involved in the conversion of nitrile-containing compounds into ammonia and organic acids. Although they are widespread in prokaryotes, nitrile hydratases have only been reported in two eukaryotes: the choanoflagellate Monosiga brevicollis and the stramenopile Aureococcus anophagefferens. The nitrile hydratase gene in M. brevicollis was believed to have arisen by lateral gene transfer from a prokaryote, and is a fusion of beta and alpha nitrile hydratase subunits. Only the alpha subunit has been reported in A. anophagefferens. Methodology/Principal Findings Here we report the detection of nitrile hydratase genes in five eukaryotic supergroups: opisthokonts, amoebozoa, archaeplastids, CCTH and SAR. Beta-alpha subunit fusion genes are found in the choanoflagellates, ichthyosporeans, apusozoans, haptophytes, rhizarians and stramenopiles, and potentially also in the amoebozoans. An individual alpha subunit is found in a dinoflagellate and an individual beta subunit is found in a haptophyte. Phylogenetic analyses recover a clade of eukaryotic-type nitrile hydratases in the Opisthokonta, Amoebozoa, SAR and CCTH; this is supported by analyses of introns and gene architecture. Two nitrile hydratase sequences from an animal and a plant resolve in the prokaryotic nitrile hydratase clade. Conclusions/Significance The evidence presented here demonstrates that nitrile hydratase genes are present in multiple eukaryotic supergroups, suggesting that a subunit fusion gene was present in the last common ancestor of all eukaryotes. The absence of nitrile hydratase from several sequenced species indicates that subunits were lost in multiple eukaryotic taxa. The presence of nitrile hydratases in many other eukaryotic groups is unresolved due to insufficient data and taxon sampling. The retention and expression of the gene in distantly related eukaryotic species suggests that it plays an important metabolic role. The novel family of eukaryotic nitrile hydratases presented in this paper represents a promising candidate for research into their molecular biology and possible biotechnological applications.
A New 4-Hydroxyphenylcyanide Nitrilases from Pseudomonas Sp. and Its Catalytic Properties

曹明乐, 姜兴林, 张海波, 咸漠, 徐鑫, 刘炜
Bioprocess (BP) , 2012, DOI: 10.12677/bp.2012.22012
Abstract: 腈水解酶催化的腈水解具有反应高效、条件温和、环境污染小和成本低等优点,在有机合成、材料合成、医药、食品、农业、畜牧业及环境等污染方面有着重要的应用前景。本研究利用初步活化和分步胁迫富集,通过Berthelot法高通量筛选与高压液相精细筛选获得一株底物对4-羟基苯乙腈具有较好的催化活性的菌株;经过培养基初步优化,产酶量达到28.47 U/ml;铜离子对该酶具有较强的抑制作用,酶学性质研究表明该菌株能够在pH 6.2~pH 7.3之间酶活性能够保持在最高酶活性的80%以上,在35~45范围内催化活性大于最大酶活性的80%,反应18 h后离心菌体二次催化几乎不丧失活性;该菌株在开发对羟基苯乙腈合成对羟基苯乙酸具有较高的开发价值。
Nitrilases can hydrolyze nitrile efficiently under mild conditions. The enzymatic methods have the advantages of less pollution, low cost compared with the chemical methods. Nitrilases are potentially applied in agriculture, industry, environment, and biomedicine. In this study, Berthelot method and high performance liquid chromatography were used to screen new stains for nitrilases. A nitrilase with high substrate specificity for 4-hydroxyphenylcyanide was found from Pseudomonas sp. 6-1. The stain produced 28.47 U/ml nitrilase after optimization of the culture conditions. The enzyme remained 80% activities at pH 6.6 to pH 7.6, temperature 35?C to 45?C, and it was stable after
Reaction of Nitrilimines and Nitrile Oxides with Hydrazines, Hydrazones and Oximes  [PDF]
Abdel-Rahman S. Ferwanah,Adel M. Awadallah
Molecules , 2005, DOI: 10.3390/10020492
Abstract: This review article discusses the reaction of nitrilimines and nitrile oxides with hydrazines, hydrazones, and oximes. Three reaction modes were observed. The article mainly covers our work published over the last fifteen years, in which interesting heterocyles such as oxadiazoles, triazoles, and tetrazines were synthesized and fully characterized.
Application of Bioinformatics in Researches of Industrial Biocatalysis

YU Hui-Min LUO Hui SHI Yue SUN Xu-Dong SHEN Zhong-Yao,

生物工程学报 , 2004,
Abstract: Industrial biocatalysis is currently attracting much attention to rebuild or substitute traditional producing process of chemicals and drugs. One of key focuses in industrial biocatalysis is biocatalyst, which is usually one kind of microbial enzyme. In the recent, new technologies of bioinformatics have played and will continue to play more and more significant roles in researches of industrial biocatalysis in response to the waves of genomic revolution. One of the key applications of bioinformatics in biocatalysis is the discovery and identification of the new biocatalyst through advanced DNA and protein sequence search, comparison and analyses in Internet database using different algorithm and software. The unknown genes of microbial enzymes can also be simply harvested by primer design on the basis of bioinformatics analyses. The other key applications of bioinformatics in biocatalysis are the modification and improvement of existing industrial biocatalyst. In this aspect, bioinformatics is of great importance in both rational design and directed evolution of microbial enzymes. Based on the successful prediction of tertiary structures of enzymes using the tool of bioinformatics, the undermentioned experiments, i.e. site-directed mutagenesis, fusion protein construction, DNA family shuffling and saturation mutagenesis, etc, are usually of very high efficiency. On all accounts, bioinformatics will be an essential tool for either biologist or biological engineer in the future researches of industrial biocatalysis, due to its significant function in guiding and quickening the step of discovery and/or improvement of novel biocatalysts.
Aryl nitrile oxide cycloaddition reactions in the presence of pinacol boronic acid ester  [cached]
Sarah L. Harding,Sebastian M. Marcuccio,G. Paul Savage
Beilstein Journal of Organic Chemistry , 2012, DOI: 10.3762/bjoc.8.67
Abstract: An aryl substrate with dual functionality consisting of a nitrile oxide and a pinacolyl boronate ester was prepared by mild hypervalent iodine oxidation (diacetoxyiodobenzene) of the corresponding aldoxime, without decomposition of the boronate functionality. The nitrile oxide was trapped in situ with a variety of dipolarophiles to yield aryl isoxazolines with the boronate ester function intact and available for subsequent reaction.
Spectrometric Study of the Nitrile-Ketenimine Tautomerism  [PDF]
Hebe Saraví Cisneros,Sergio Laurella,Danila L. Ruiz,Agustín Ponzinibbio,Patricia E. Allegretti,Jorge J. P. Furlong
International Journal of Spectroscopy , 2009, DOI: 10.1155/2009/408345
Abstract: Mass spectrometry is used to evaluate the occurrence of the nitrile-ketenimine tautomerism. Mass spectra of two differently substituted nitriles, ethyl-4,4-dicyano-3-methyl-3-butenoate and diethyl-2-cyano-3-methyl-2-pentenodiate are examined looking for common mass spectral behaviors. Ion fragmentation assignments for specific tautomers allow to predict the presence of the corresponding structures. Additionally, the mass spectrum and nuclear magnetic resonance spectra of ethyl-4,4-dicyano-2,2-diethyl-3-methyl-3-butenoate and that of the corresponding amination product support the occurrence of the ketenimine tautomer in the equilibrium.
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