Download or read book Toward the Development of a Biocatalytic Process for the Production of Beta aryl beta amino Acids written by Nishanka Dilini Ratnayake and published by . This book was released on 2015 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Enantioselective Synthesis of Beta Amino Acids written by Eusebio Juaristi and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of a C nucleophilic Intermediate for the Biocatalytic Synthesis of beta hydroxy amino Acids written by Anthony Meza (Ph.D.) and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Enzymes are biological catalysts that perform diverse chemical transformations. Many enzymes have been utilized as biocatalysts in preparation and manufacturing of consumer goods and chemicals. However, enzymes that catalyze well controlled C-C bond formation on a broad range of substrates are sparse in biocatalysis. In this work, we describe the characterization and implementation of ObiH, an L-Threonine transaldolases (LTTA), for the biocatalytic assembly of [beta]-hydroxy-[alpha]-amino acids. LTTAs are a poorly characterized class of pyridoxal-5'-phosphate (PLP) dependent enzymes. We describe the catalytic mechanism of ObiH, an LTTA present in the biosynthesis of the [beta]-lactone natural product obafluorin. UV-vis spectroscopic analysis reveals that ObiH catalyzes the retro-aldol cleavage of L-threonine (Thr) to form a remarkably persistent C-nucleophilic intermediate, with a half-life of ~ 3 h. Protonation of this intermediate is kinetically disfavoured, enabling on-cycle reactivity with diverse aldehydes to form [beta]-hydroxy-[alpha]-amino acids. However, access to the native electrophile class for ObiH, [alpha]-aryl aldehydes, is precluded due to the innate reactivity of these molecules. We therefore developed a chemoenzymatic platform to generate [alpha]-aryl aldehydes in situ; through the action of styrene oxide isomerase (SOI) with styrene oxide analogs. The two-enzyme cascade was successful at generating and capturing unstable [alpha]-aryl aldehyde intermediates under aqueous conditions. Co-expression of both enzymes in E. coli yields a whole cell biocatalyst capable of synthesizing a variety of stereopure [beta]-hydroxy-[alpha]-amino acids. We used isotopically labelled substrates to probe the mechanism of SOI, which we show to catalyze a concerted isomerization featuring a stereospecific 1,2-hydride shift. The mechanistic investigation of ObiH and SOI provide a thorough analysis of the reactivity observed through this two-enzyme cascade and demonstrates that [alpha]-aryl aldehyde intermediates are useful synthons in C2C bond forming cascades. Lastly, we highlight the unique activity of ObiH with the synthesis of tertiary [beta]-hydroxy-[alpha]-amino acids by intercepting ketone electrophiles with the kinetically shielded C-nucleophilic intermediate.
Download or read book Asymmetric Synthesis of Beta aryl beta amino Acids and Completion of Total Synthesis of jasplakinolide written by Kent Sinching Chu and published by . This book was released on 1991 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biocatalytic Preparation of Amino Acids written by Vivek Kothari and published by Daya Books. This book was released on 2007 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amino Acids Are The Molecular Units That Make Up Proteins. All Proteins Are Various Compositions Of Twenty Specific Naturally Occurring Amino Acids. Amino Acids Are Found In All Foods Except Oil. There Are About Eighty Amino Acids Found In Nature, But Only Twenty To Twenty-Nine Are Required For Human Growth. Amino Acids Play A Pivotal Role In Living Systems, And Therefore Synthetic Amino Acids Have Been Of Significant Interest To Researchers Working Towards The Understanding And Modification Of Physiological Processes. Currently, The Amino Acids Used In Amino Acid Products Are Mainly Manufactured By Biocatalytic Methods. The Book Presents Detailed Discussion Of The Preparation Of Amino Acids By Biocatalysis. It Provides Examples Of Recently Developed Biocatalytic Methods For The Production Of Amino Acids And Its Derivatives. It Offers Upper Level Students And Professionals An Essential Resource For Pharmaceutical Development, Medicinal Chemistry And Biochemistry. Contents Chapter 1: Basics Of Biocatalysis; Chapter 2: Production Of Amino Acids; Chapter 3: Asymmetric Synthesis Of Amino Acids; Chapter 4: Amino Acids And Derivatives; Chapter 5: Strategies For Efficient Biocatalysis; Chapter 6: Synthesis Of Cage Amino Acids; Chapter 7: Types Of B-Amino Acids; Chapter 8: Extremophiles And Extremozymes; Chapter 9: Immobilised Enzymes; Chapter 10: Enzymatic Peptide Synthesis; Chapter 11: Synthesis Of Enantiomerically Pure (S)-Amino Acids And (R)-Amines; Chapter 12: Cloning And Sequence Analysis; Chapter 13: Bioseparation And Biocatalytic Applications.
Download or read book Towards a Modified Hydantoinase Process for the Chemoenzymatic Production of Chiral Beta amino Acids Substrate Synthesis Screening and Characterization of Novel Biocatalysts written by Ulrike Engel and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Towards a modified hydantoinase process for the chemoenzymatic production of chiral amino beta amino acids written by Ulrike Engel and published by . This book was released on 2012 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Discovery and Properties of Enzymes for Biocatalytic Production of beta amino Acids written by Rijksuniversiteit Groningen and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biocatalysis of Aromatic beta hydroxy alpha amino Acids Via Regio and Stereoselective Amination of Trans 3 arylglycidates Using a Phenylalanine Aminomutase written by Prakash Kumar Shee and published by . This book was released on 2020 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biocatalytic Production of Amino Acids and Derivatives written by J. David Rozzell and published by Wiley-Interscience. This book was released on 1993-11-04 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A richly illustrated text designed to provide examples of recently developed methods for the production of amino acids, derivatives and biocatalysts. Describes such new technologies as development of membrane reactors, use of enzymes in nonaqueous solvents, application of recombinant DNA techniques for the cloning and expression of genes, newly discovered enzymes and microbial strains and immobilized biocatalytic systems.
Download or read book Development of Bioprocesses for the Production of Biocatalysts Used in the Synthesis of Amino Acids and Amines written by Brian Hugh Wilson Griffin and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research in to enzyme catalysis has enormously enriched the success of biological organic synthesis; particularly in the last decade, remarkable progress in biological catalysis has taken place leading to the application of enzymes to a wider extent in industrial processes. The benefits of establishing enzymes as industrial catalysts are founded on the need to develop a 'clean' and 'pure' technology which carry out isomer and region selective reactions; generate or transform pure isomers compared with racemic mixtures and produce pure compounds in comparison with mixtures of by-products often arising from conventional chemical synthesis. With the onset of molecular biology and genetics, the manufacturing of high value proteins in recombinant host cells has become commonplace; nevertheless, there needs to be a better understanding of the optimum conditions for the production of every recombinant protein. In this study, the over expression of an industrially important amine oxidase - D-Amino Acid Oxidase (DAAO) - was attempted using two different expression systems: Escherichia coli and Pichia pastoris in order to establish the optimum conditions for industrial production. Amine oxidases exhibit stereoselectivity; ergo they can theoretically be used for the deracemisation of nonopticallypure mixtures of amines leading to optically pure amines of high value.Furthermore, DAAO is involved in the production of 7-aminocephalosporanic acid (7-ACA) from cephalosporin c (CPC), which can be used in the synthesis of novel cephalosporin antibiotic derivatives. In order to accelerate development of these new antibiotics DAAO must be readily available. Overexpression of DAAO in E. coli was studied under varying experimental conditions in order to ascertain the best conditions for enzymatic activity whilst simultaneously investigating the variations between both defined and complex media to understand suitability for scale-up.Although E. coli is still regarded as the 'go to' organisms for initial laboratory scale up the methylotrophic yeast P. pastoris is considered an industrial workhorse for the production of recombinant proteins and thus the expression of DAAO was also investigated to ascertain how enzyme activities are affected by this expression system. Furthermore, the supplementation of media with different nutrient sources of varying complexity was investigated, as was the implementation of co-feeding inorder to improve carbon flux during recombinant protein production. Finally, the oxygen availability was investigated in order to gain important understandings on its effects on microbial physiology and DAAO activity.
Download or read book Catalytic and Biocatalytic Methods for the Efficient Synthesis of Biologically Relevant Non Proteinogenic Amino Acids written by Anke Lemke and published by Cuvillier Verlag. This book was released on 2014-04-29 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-proteinogenic amino acids are often important constituents of biologically potent natural products. The synthesis of these amino acids is often time-consuming, non-trivial and not sustainable. Thus, the central topic of this work was the formation of unusual amino acid structures by biocatalytic and catalytic methods. For the elucidation of the biosynthetic pathway of Streptomyces-produced muraymycins and related natural products, a ‘biosynthetic tool kit’ was compiled and prepared. This does not only comprehend the completed synthesis of deuterium-labeled compounds, such as (3R)- and (3S)-3-hydroxy-[5-2H]-l-arginine and other potential intermediates with a nucleosidic structure, but it also includes the development of fermentation methodology including the possibility to detect the muraymycin derivatives by LC MS. Furthermore, different synthetic routes with catalytic key steps for the preparation of the non-proteinogenic amino acid enduracididine were investigated.
Download or read book Synthesis of Branched alpha and amino beta amino Acids Using C nucleophile Additions to Imines and Nitrones written by Alevtina Baskakova and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Artificial peptides, containing alpha- and/or beta-amino acids with bulky substituents, can potentially possess some unusual properties, for example, decreased conformational ability or formation of stable secondary structures. Therefore, the preparation of such unnatural amino acids is of high interest. In this thesis, a route to enantiomerically pure 1-adamantylglycine was developed. The crucial step was the highly stereoselective addition of adamantylmagnesium bromide to the C=N bond of 2,3-O-cyclohexylidene-D-glyceraldehyde N-benzylnitrone effected in the presence of Lewis acid. Finally, 1-adamantylglycine was synthesized in 28 % yield over 6 steps. The routes to 9-aminofluorenylacetic and beta-aminobeta, beta-diphenylpropionic acids were proposed and they consist in the addition of allyl Grignard reagents to imines with various protecting groups, followed by oxidative transformation of the allyl group. Also some procedures for the preparation of 3,3-disubstituted 4-azetidinones, direct precursors of the corresponding beta-branched beta-amino acids, have been investigated.
Download or read book The Synthesis and Applications of Sulfoxide Ligands and Methodology Development Towards Beta Amino Acid Incorporation in Peptides written by Priscilla Leung and published by . This book was released on 2011 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: The incorporation of beta-amino acid residues into polypeptides has resulted in new foldamers whose structures and enhanced stability provide interesting opportunities for new biological applications. A novel strategy for an iterative peptide synthesis involving beta-amino acids will be proposed. Lastly, a hydroamidation-type strategy for the construction of beta 3-amino acids, or more specifically of beta-(N-acylamino)acrylates, will be presented as preliminary work towards the goal of dipeptide synthesis.The use of sulfoxide ligands for transition metal catalyzed transformations has recently been brought to the forefront in organic chemistry. The synthesis of a series of tri- and disulfoxides will be presented, and their applications investigated. Their use in rhodium catalyzed 1,4-additions of phenylboronic acid to 2-cyclohexen-1-one result in enantioselectivities up to 80%.
Download or read book Redox Biocatalysis written by Daniela Gamenara and published by John Wiley & Sons. This book was released on 2012-09-18 with total page 681 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paves the way for new industrial applications using redox biocatalysis Increasingly, researchers rely on the use of enzymes to perform redox processes as they search for novel industrial synthetic routes. In order to support and advance their investigations, this book provides a comprehensive and current overview of the use of redox enzymes and enzyme-mediated oxidative processes, with an emphasis on the role of redox enzymes in chemical transformations. The authors examine the full range of topics in the field, from basic principles to new and emerging research and applications. Moreover, they explore everything from laboratory-scale procedures to industrial manufacturing. Redox Biocatalysis begins with a discussion of the biochemical features of redox enzymes as well as cofactors and cofactor regeneration methods. Next, the authors present a variety of topics and materials to the research and development of full-scale industrial applications, including: Biocatalytic applications of redox enzymes such as dehydrogenases, oxygenases, oxidases, and peroxidases Enzyme-mediated oxidative processes based on biocatalytic promiscuity All the steps from enzyme discovery to robust industrial processes, including directed evolution, high-throughput screening, and medium engineering Case studies tracing the development of industrial applications using biocatalytic redox reactions Each chapter ends with concluding remarks, underscoring the key scientific principles and processes. Extensive references serve as a gateway to the growing body of research in the field. Researchers in both academia and industry will find this book an indispensable reference for redox biotransformations, guiding them from underlying core principles to new discoveries and emerging industrial applications.
Download or read book Novel Transaminases for the Biocatalytic Synthesis of Aromatic Amino beta amino Acids written by Birgit Brucher and published by . This book was released on 2012 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Novel Biocatalytic Routes to Optically Active Amino Alcohols and Alfa Beta amino Acids written by Botond Nagy and published by . This book was released on 2017 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: