Enzymatic production

Production by Isolation. Natural cysteine and cystine have been manufactured by hydrolysis and isolation from keratin protein, eg, hair and feathers. Today the principal manufacturing of cysteine depends on enzymatic production that was developed in the 1970s (213). 

Fig. 6. Representative chemical reactions in the enzymatic production of amino acids.

Figure A8.4 Commercial process for the enzymatic production of L- and D-amino acids from N-acetyl-D,L-amino acids.

Enzymatic Production of Bacterial Polysaccharides, M. Stacey, Nature. 149 (1942) 639. 

Recently, an environmentally benign and volume efficient process for enzymatic production of alkanolamides has been described where CALB catalyzes the amidation of lauric acid and ethanolamine in the absence of solvent, at 90 °C, to keep the reactants in a liquid state and to remove the water [18]. The enzyme was both very active and stable under the reaction conditions, with about half of the activity remaining after two weeks, obtaining the final amide with a 95% yield (Scheme 7.6). 

A model developed by Leksawasdi et al. [11,12] for the enzymatic production of PAC (P) from benzaldehyde (B) and pyruvate (A) in an aqueous phase system is based on equations given in Figure 2. The model also includes the production of by-products acetaldehyde (Q) and acetoin (R). The rate of deactivation of PDC (E) was shown to exhibit a first order dependency on benzaldehyde concentration and exposure time as well as an initial time lag [8]. Following detailed kinetic studies, the model including the equation for enzyme deactivation was shown to provide acceptable fitting of the kinetic data for the ranges 50-150 mM benzaldehyde, 60-180 mM pyruvate and 1.1-3.4 U mf PDC carboligase activity [10]. 

Ji X-B, TC Hollocher (1988) Mechanism for nitrosation of 2,3-diaminonaphthalene by Escherichia coli enzymatic production of NO followed by Oj-dependent chemical nitrosation. Appl Environ Microbiol 54 1791-1794. 

A homogeneous electrochemical enzyme immunoassay for 2,4-dinitrophenol-aminocaproic acid (DNP-ACA), has been developed based on antibody inhibition of enzyme conversion from the apo- to the holo- form Apoglucose oxidase was used as the enzyme label. This enzyme is inactive until binding of flavin adenine dinucleotide (FAD) to form the holoenzyme which is active. Hydrogen peroxide is the enzymatic product which is detected electrochemically. Because antibody bound apoenzyme cannot bind FAD, the production of HjOj is a measure of the concentration of free DNP-ACA in the sample. 

Nonnucleoside reverse transcriptase inhibitor (NNRTI) A noncompetitive inhibitor of the viral reverse transcriptase enzyme that binds to the active site of the enzyme itself, rather than by terminating the enzymatic product. NNRTIs are only active against human immunodeficiency virus-1. 

Tang, G. et al. (1991). Characterization of (3-apo-13 carotenone and (3-apo-14 -carotenal as enzymatic products of the excentric cleavage of (3-carotene. Biochemistry 30 9829-9834. 

Schmidt, E., Ghisalba, O., Gygax, D. and Sedelmeier, G. (1992) Optimization of a process for the enzymatic production of fA )-2-hyroxy-4-phenyl butyric acid - an intermediate for inhibitors of angiotensin converting enzymes. Journal of Biotechnology, 24, 315-327. 

Bayer, T. (2004) 7-Aminocephalosporanic acid - chemical versus enzymatic production process, in Asymmetric Catalysis on Industrial Scale (2004), (eds H.-U. Blaser and E. Schmidt), Wiley-VCH Verlag GmbH, 117-130. 

M. Quirasco, A. Lopez-Munguia, V. Pelenc, M. Remaud, F. Paul, and P. Monsan, Enzymatic production of glucooligosaccharides containing a-(1 —> 2) osidic bonds. Potential application in nutrition, Ann. NY Acad. Sci., 750 (1995) 317-320. 

J. W. Yun and S. K. Song, Enzymatic production of fructooligosaccharides from sucrose, in C. Bucke, (Ed.), Methods in Biotechnology—Carbohydrate Biotechnology Protocols, Humana Press, New Jersey, 1999, pp. 141-151. 

In AChE-based biosensors acetylthiocholine is commonly used as a substrate. The thiocholine produced during the catalytic reaction can be monitored using spectromet-ric, amperometric [44] (Fig. 2.2) or potentiometric methods. The enzyme activity is indirectly proportional to the pesticide concentration. La Rosa et al. [45] used 4-ami-nophenyl acetate as the enzyme substrate for a cholinesterase sensor for pesticide determination. This system allowed the determination of esterase activities via oxidation of the enzymatic product 4-aminophenol rather than the typical thiocholine. Sulfonylureas are reversible inhibitors of acetolactate synthase (ALS). By taking advantage of this inhibition mechanism ALS has been entrapped in photo cured polymer of polyvinyl alcohol bearing styrylpyridinium groups (PVA-SbQ) to prepare an amperometric biosensor for... 

The subject of biochemical reactions is very broad, covering both cellular and enzymatic processes. While there are some similarities between enzyme kinetics and the kinetics of cell growth, cell-growth kinetics tend to be much more complex, and are subject to regulation by a wide variety of external agents. The enzymatic production of a species via enzymes in cells is inherently a complex, coupled process, affected by the activity of the enzyme, the quantity of the enzyme, and the quantity and viability of the available cells. In this chapter, we focus solely on the kinetics of enzyme reactions, without considering the source of the enzyme or other cellular processes. For our purpose, we consider the enzyme to be readily available in a relatively pure form, off the shelf, as many enzymes are. 

For biochemical assays, /iPLC allows direct quantification of substrates and products using a much-valued separation-based approach that allows development and optimization of challenging enzymatic assays faster and with fewer false positives. The separation-based approach employed by /iPI. C dramatically reduces assay development time from months to a few days. Since substrate and enzymatic products are separated prior to detection, /iPLC enables development of difficult assays, such as analyzing enzymes with low kinetic activities and enzymes that cannot be analyzed on existing platforms. 

Nakamura, T., et al. (1993). Enzymatic production of hypoallergenic peptides from... 

The detection of very low levels of alkaloids is a fundamental requirement for the analysis of cell contents and enzymatic products. One of the important compounds is of course vindoline (3), and a combined French... 

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