Aspartate fumaric acid

Fumaric acid occurs naturally in many plants and is named after Fumaria officinalis, a climbing aimual plant, from which it was first isolated. It is also known as (E)-2-butenedioic acid, aHomaleic acid, boletic acid, Hchenic acid, or /n j -l,2-ethylenedicarboxylic acid. It is used as a food acidulant and as a raw material in the manufacture of unsaturated polyester resins, quick-setting inks, furniture lacquers, paper sizing chemicals, and aspartic acid [56-84-8]. 

Enzymatic Process. Chemically synthesized substrates can be converted to the corresponding amino acids by the catalytic action of an enzyme or the microbial cells as an enzyme source, t - Alanine production from L-aspartic acid, L-aspartic acid production from fumaric acid, L-cysteine production from DL-2-aminothiazoline-4-catboxyhc acid, D-phenylglycine (and D-/> -hydtoxyphenylglycine) production from DL-phenyUiydantoin (and DL-/)-hydroxyphenylhydantoin), and L-tryptophan production from indole and DL-serine have been in operation as commercial processes. Some of the other processes shown in Table 10 are at a technical level high enough to be useful for commercial production (24). Representative chemical reactions used ia the enzymatic process are shown ia Figure 6. 

L-aspartic acid fumaric acid + NH aspartase E. coii ... 

Co(lII) perchlorate oxidations of succinic, aspartic, maleic and fumaric acids all obey the rate expression ... 

Fumaric acid to L-aspartic acid, L-aspartic acid to L-alanine Enzymatic resolution of methyl ester of (+/-) trans 4- methoxy-... 

An important problem in emulsified organic-aqueous systems is that of scale-up, which is concerned with the realization of stable emulsions and the separation of phases after the reaction. The use of biphasic membrane systems that contain the enzyme and keep the two phases separated is likely to solve this problem. In the case of 5-naproxen an ee of 92% has been demonstrated without any decay in activity over a period of two weeks of continuous operation. A number of examples of biocatalytic membrane reactors have been provided by Giorno and Drioli (2000) and include the conversion of fumaric acid to L-aspartic acid, L-aspartic acid to L-alanine, and cortexolone to hydrocortisone and prednisolone. 

Many enzymes have absolute specificity for a substrate and will not attack the molecules with common structural features. The enzyme aspartase, found in many plants and bacteria, is such an enzyme [57], It catalyzes the formation of L-aspartate by reversible addition of ammonia to the double bond of fumaric acid. Aspartase, however, does not take part in the addition of ammonia to any other unsaturated acid requiring specific optical and geometrical characteristics. At the other end of the spectrum are enzymes which do not have specificity for a given substrate and act on many molecules with similar structural characteristics. A good example is the enzyme chymotrypsin, which catalyzes hydrolysis of many different peptides or polypeptides as well as amides and esters. 

By far, the best asymmetric synthesis is done in nature by enzymes7). These have also found industrial application8, e.g. the stereospecific amination of fumaric acid (10) to (S)-aspartic acid (11) ... 

L-aspartic acid by ammonia addition to fumaric acid by aspartase (from E. coli)... 

Owing to the commercialization of Aspartame the demand for i-aspartic acid increased steeply. i-Aspartate can be produced by enantioselective addition of ammonia to fumaric acid catalyzed by aspartase (E.C. 4.3.1.1) (Figure 7.17). 

Because of the difficulties of stabilizing the pH at the pH optimum of 6.0 owing to liberation of C02, a loop reactor was developed which keeps the C02 dissolved at lObar and thus helps to stabilize the pH. Co-immobilization of E. coli and Ps. dacunhae cells for direct production of L-alanine from fumaric acid was not successful because E. coli cells work best at a pH of 8.5, in comparison with a pH of 6.0 for Ps. dacunhae cells and the decarboxylase. The sequential process has been run since 1982. The high enantioselectivity of L-aspartate-/kdecarboxylase (ADC) led to a process, in 1989, in which inexpensive DL-aspartate was converted to L-alanine and D-aspartate [Eq. (7.1)] the latter commands interest for synthetic penicillins ... 

Aspartic acid Fumaric acid 2-Amino-1,4-butanediol, 3-aminotetrahydrofuran, amino-2-pyrrolidone, aspartic anhydride Werpy and Petersen 2004... 

Acetic acid Acetaldehyde Acetone L-Alanine l-Alanine ion L-Alaninate ion L-Arginine dl-Aspartic acid L-Aspartic acid L-Aspartic acid ion L-Aspartate ion Benzene Butyric acid Butyrate ion Carbon dioxide Citric acid Citrate ion Creatine L-Cysteine L-Cystine Ethanol Ethyl acetate Formic acid Formate ion Fumaric acid Fumarate ion a-D-Glucose p-D-Glucose Glycerol L-Glutamic acid L-Glutamate ion... 

Thus, in the action of the enzyme aspartase, fumaric acid, 39, is transformed into L-aspartic acid, 40. This process can be considered as a result of three steps ... 

Inosine 5-phosphate (XXX) was converted to adenylosuccinate [6-(succinylamino)-9-(5-0-phospho-/8-D-ribofuranosyl)purine, XXXI] which was isolated by ion-exchange chromatography and was identified by analysis and by its characteristic absorption spectrum. The stoichiometry of the reaction was also verified by isolation and determination of the reactants. Hydroxylamine could replace L-aspartate, and the product formed was isolated and tentatively identified as iV -hydroxyadenosine 5-phosphate. A crude extract of Escherichia coli B was shown to split adenylosuccinate to adenosine 5-phosphate and fumaric acid. 

In Escherichia colF and Salmonella typhimurium have been detected enzymes which split iV-[5 amino-l-(5-0-phospho-D-ribofuranosyl)-4-imida-zolecarbonyl]-L-aspartic acid to fumaric acid and 5-amino-4-imidazolecar-boxamide ribonucleotide. 

Akhtar M, Botting NP, Cohen MA Gani D (1987) Enantiospecific Synthesis of 3-Substituted Aspartic Acids via Enzymic Amination of Substituted Fumaric Acids. Tetrahedron 43 5899... 

The industrial preparation of L-aspartic acid by the amination of ( )-2-butenedioic acid (fumaric acid) made use of some form of immobilized aspartase (free cell), which were replaced by microbial whole cells, resulting in reduced costs and simplified operations 38a d. 

A variety of 3-substituted aspartic acids 7 can be prepared by stereospecific addition of ammonia to substituted fumaric acids 6 catalyzed by /(-methylaspartase (EC 4.3.1.2). The enzyme, which was first isolated from Clostridium tetanomorphum (ATCC 15920)42, aminates... 

L-aspartic acid Fumaric acid Escherichia coli (aspartase) ... 

It is also possible to convert nonchiral readily available industrial organic chemicals into valuable chiral natural-analogue products. This is demonstrated by the conversion of achiral fumaric acid to L(-)-malic acid with fumarase as the active enzyme. The same compound is converted to the amino acid L(-h)-aspartic acid by Escherichia bacteria that contain the enzyme aspartase. If pseudomonas bacteria are added, another amino acid L-alanine is formed (Eq. 9.10). 

The photochemical carboxylation of pyruvic acid by this process is endergonic by about AG° = 11.5 kcal mol and represents a true uphill photosynthetic pathway. The carbon dioxide fixation product can then act as the source substrate for subsequent biocatalyzed transformations. For example, photogenerated malic acid can act as the source substrate for aspartic acid (Figure 35). In this case, malic acid is dehydrated by fumarase (Fum) and the intermediate fumaric acid is aminated in the presence of aspartase (Asp) to give aspartic acid. 

A biocatalytic enantioselective addition of ammonia to a C=C bond of an a,)9-unsaturated compound, namely fumaric acid, makes the manufacture of L-aspartic acid possible on an industrial scale. This process, which is applied by, e. g., Kyowa Hakko Kogyo and Tanabe Seiyaku, is based on the use of an aspartate ammonia lyase as a biocatalyst [119]. Another comparable reaction is the asymmetric biocatalytic addition of ammonia to trans-cinnamic acid, which represents a technically feasible process for the production of L-phenyl-alanine [120]. 

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