287955-93-5Relevant academic research and scientific papers
Creation of a productive, highly enantioselective nitrilase through gene site saturation mutagenesis (GSSM)
DeSantis, Grace,Wong, Kelvin,Farwell, Bob,Chatman, Kelly,Zhu, Zoulin,Tomlinson, Geoff,Huang, Hongjun,Tan, Xuqiu,Bibbs, Lisa,Chen, Pei,Kretz, Keith,Burk, Mark J.
, p. 11476 - 11477 (2003)
Gene site saturation mutagenesis (GSSM) technology is applied for the directed evolution of a nitrilase. The nitrilase effectively catalyzes the desymmetrization of the prochiral substrate 3-hydroxyglutaronitrile to afford (R)-4-cyano-3-hydroxybutyric acid, a precursor to the valuable cholesterol-lowering drug Lipitor. The discovered wild-type enzyme effectively performs the reaction at the industrially relevant 3 M substrate concentration but affords a product enantiomeric excess of only 87.6% ee. Through GSSM, a mutagenesis technique that effects the combinatorial saturation of each amino acid in the protein to each of the other 19 amino acids, combined with a novel high-throughput mass spectroscopy assay, a number of improved variants were identified, the best of which is the Ala190His mutant that yields product enantiomeric excess of 98.5% at 3 M substrate loading and a volumetric productivity of 619 g L-1 d-1. Copyright
Nitrilases, nucleic acids encoding them and methods for making and using them
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Page/Page column 98-100, (2016/01/09)
The invention relates to nitrilases and to nucleic acids encoding the nitrilases. In addition methods of designing new nitrilases and method of use thereof are also provided. The nitrilases have increased activity and stability at increased pH and temperature.
Substrate evaluation of rhodococcus erythropolis SET1, a nitrile hydrolysing bacterium, demonstrating dual activity strongly dependent on nitrile sub-structure
Coady, Tracey M.,Coffey, Lee V.,O'Reilly, Catherine,Lennon, Claire M.
supporting information, p. 1108 - 1116 (2015/02/19)
Assessment of Rhodococcus erythropolis SET1, a novel nitrile hydrolysing bacterial isolate, has been undertaken with 34 nitriles, 33 chiral and 1 prochiral. These substrates consist primarily of β-hydroxy nitriles with varying alkyl and aryl groups at the β position and containing in several compounds different substituents α to the nitrile. In the case of β-hydroxy nitriles without substitution at the α position, acids were the major products obtained, along with recovered nitrile after biotransformation, as a result of suspected nitrilase activity of the isolate. Unexpectedly, amides were found to be the major hydrolysis product when the β-hydroxy nitriles possessed a vinyl group at this position. To probe this behaviour further, additional related substrates were evaluated containing electron-withdrawing groups at the α position, and amide was also observed upon biotransformation in the presence of SET1. Therefore this novel isolate has also demonstrated NHase activity with nitriles that appears to be substrate-dependent.
Nitrilase-catalysed desymmetrisation of 3-hydroxyglutaronitrile: Preparation of a statin side-chain intermediate
Bergeron, Sophie,Chaplin, David A.,Edwards, John H.,Ellis, Brian S. W.,Hill, Catherine L.,Holt-Tiffin, Karen,Knight, Jonathan R.,Mahoney, Thomas,Osborne, Andrew P.,Ruecroft, Graham
, p. 661 - 665 (2012/12/22)
An efficient, scaleable synthesis of ethyl (R)-4-cyano-3-hydroxybutyrate, a potential intermediate in the synthesis of Atorvastatin (Lipitor), has been developed. The three-stage process starts with reaction of low-cost epichlorohydrin with cyanide to give 3-hydroxyglutaronitrile (3-HGN). The second stage utilises a nitrilase-catalysed desymmetrisation of 3-HGN. The nitrilase reaction has been optimized to work at 3 M (330 g/L) substrate concentration, pH 7.5,27 °C. Under these conditions, with an enzyme loading of 6 wt %, 100% conversion and 99% ee product is obtained in 16 h. This material is then esterified to give the target compound, ethyl (R)-4-cyano-3-hydroxybutyrate. The cost-effectiveness of the process is determined by three factors: use of a low-cost starting material, the introduction of the chiral centre by desymmetrisation as opposed to kinetic resolution, and the use of Pfenex Expression Technology to allow a lower-cost supply of biocatalyst.
A novel reagent for the chemical phosphorylation of oligonucleotides
Leuck, Michael,Vagle, Kurt E.,Roach, J. Shawn,Wolter, Andreas
, p. 321 - 324 (2007/10/03)
A novel phosphoramidite reagent was developed to convert terminal hydroxyl groups of oligonucleotides into phosphate monoesters. The reagent's appearance as a solid foam is advantageous for its manipulation and handling in solid phase synthesis and improves its thermal stability.
Novel phosphorylation reagents for improved processes to convert terminal hydroxyl groups of oligonucleotides into phosphate monoesters
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Page 12; 13, (2008/06/13)
The present invention discloses novel phosphoramidite reagents for use in oligonucleotide synthesis. The present invention further discloses novel methods for the conversion of terminal hydroxyl groups of oligonucleotides into phosphate monoesters. By emp
PROCESSES FOR MAKING (R)-ETHYL 4-CYANO-3-HYDROXYBUTYRIC ACID
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Page 20, (2008/06/13)
The invention provides novel processes for making ethyl-4-cyano-3-hydroxybutyrate, e.g., (R)-ethyl 4-cyano-3-hydroxybutyric acid, and 4-cyano-3-hydroxybutyric acid. The invention provides protocols for making and 4-cyano-3-hydroxybutyric acid and ethyl-4-cyano-3-hydroxybutyrate by whole cell processes, cell lysate processes, "one pot processes" and "multi-pot" processes using a variety of parameters.
Process for preparing(R)-4-cyano-3-hydroxybutyric acid ester
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, (2008/06/13)
The present invention relates to a process for preparing (R)-4-cyano-3-hydroxybutyric acid ester derivatives and more particularly, to a process for preparing optically pure (R)-4-cyano-3-hydroxybutyric acid ester derivatives expressed by formula (1) in high yield by performing cyanation and sequential esterification of (S)-3,4-epoxybutyric acid salt as a starting material. In said formula, R represents linear or branched alkyl group with 1?5 carbon atoms or benzyl group.
An enzyme library approach to biocatalysis: Development of nitrilases for enantioselective production of carboxylic acid derivatives
DeSantis, Grace,Zhu, Zuolin,Greenberg, William A.,Wong, Kelvin,Chaplin, Jenny,Hanson, Sarah R.,Farwell, Bob,Nicholson, Lawrence W.,Rand, Cynthia L.,Weiner, David P.,Robertson, Dan E.,Burk, Mark J.
, p. 9024 - 9025 (2007/10/03)
The discovery, from Nature, of a large and diverse set of nitrilases is reported. The utility of this nitrilase library for identifying enzymes that catalyze efficient production of valuable hydroxy carboxylic acid derivatives is demonstrated. Unprecedented enantioselectivity and substrate scope are highlighted for three newly discovered and distinct nitrilases. For example, a wide array of (R)-mandelic acid derivatives and analogues were produced with high rates, yields, and enantiomeric excesses (95-99% ee). We also have found nitrilases that provide direct access to (S)-phenyllactic acid and other aryllactic acid derivatives, again with high yields and enantioselectivities. Finally, different nitrilases have been discovered that catalyze enantiotopic hydrolysis of 3-hydroxyglutaronitrile to afford either enantiomer of 4-cyano-3-hydroxybutyric acid with high enantiomeric excesses (>95% ee). The first enzymes are reported that effect this transformation to furnish the (R)-4-cyano-3-hydroxybutyric acid which is a precursor to the blockbuster drug Lipitor. Copyright
