Pyruvic acid Ammonium salt

To HEPES buffer (100 mL, 200 mM, pH 7.5) were added ManNAc 15 (1.44 g, 6 mmol), PEP sodium salt (1.88 g, 8 mmol), pyruvic acid sodium salt (1.32 g, 12 mmol), CMP (0.64 g, 2 mmol), ATP (11 mg, 0.02 mmol), pyruvate kinase (300 U), myokinase (750 U), inorganic pyrophosphatase (3 U), /V-acctylneuraminic acid aldolase (100 U), and CMP-sialic acid synthetase (1.6 U). The reaction mixture was stirred at room temperature for 2 days under argon, until CMP was consumed. The reaction mixture was concentrated by lyophilization and directly applied to a Bio-Gel P-2 column (200-400 mesh, 3 x 90 cm), and eluted with water at a flow rate of 9 mL/h at 4°C. The CMP-NeuAc fractions were pooled, applied to Dowex-1 (formate form), and eluted with an ammonium bicarbonate gradient (0.1-0.5 M). The CMP-NeuAc fractions free of the nucleotides were pooled and lyophilized. Excess ammonium bicarbonate was removed by addition of Dowex 50W-X8 (H+ form) to the stirred solution of the residual powder until pH 7.5. The resin was filtered off and the filtrate was lyophilized to yield the ammonium salt of CMP-NeuAc 17 (1.28 g, 88%). 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

In contrast, amino acid dehydrogenases comprise a well-known class of enzymes with industrial apphcations. An illustrative example is the Evonik (formerly Degussa) process for the synthesis of (S)-tert-leucine by reductive amination of trimethyl pyruvic acid (Scheme 6.12) [27]. The NADH cofactor is regenerated by coupling the reductive amination with FDH-catalyzed reduction of formate, which is added as the ammonium salt. 

A synthesis of acetylalanine, from which alanine can be obtained by hydrolysis, was described in 1900 by de Jong. Pyruvic acid was neutralised with ammonium carbonate there was a considerable rise in temperature, carbon dioxide was evolved and the ammonium salt of acetylalanine crystallised out The explanation of this reaction is based upon Erlenmeyer and Kunlin s synthesis of phenylalanine from phenyl-pyruvic acid and it proceeds as follows —... 

In yet another study the thiazolium ring was attached to a macrotricyclic quaternary ammonium ion 9, bearing several positive charges to determine if rate accelerations of pyruvate decarboxylation could be observed46. Such rate accelerations could indeed be observed, especially for phenylpyruvic acid as a substrate. In addition, lumiflavin-3-acetic acid as a potential oxidant of the intermediate (see the oxidative decarboxylation pathway in Scheme 1) was shown to be reduced by the pyruvic acid analog in the presence of DBU in ethanol and the macrotricyclic quaternary ammonium salt. 

Subsequently, Krampitz (50b) reported that pyruvic, phenylpyruvic, or oxalacetic acid can replace a-ketoglutaric acid in the amination system to form alanine, phenylalanine, and aspartic acid, respectively. Urea could be replaced with nicotinamide, adenine, adenosine, AMP, ADP, ATP, polyadenylic acid, RNA, DNA, and ammonium salts. 

To illustrate the methods, a culture medium that contains indole, pyruvic acid, tyrosine phenollyase and an ammonium salt, as well as the usual buffers and salts, will accumulate L-tryptophan or will produce an indole-substituted L-tryptophan if indole itself is replaced by a substituted indole. L-Dopa formed in a system employing tyrosinase from Aspergillus terreus provides a further example of this approach (Chattopadhyay and Das, 1990). 

Fig. 1.8 Asaccharolytic fermentation produces ammonia and short-chain fatty acids. This group of fermentations by oral bacteria utilizes proteins, which are converted to peptides and amino acids. The free amino acids are then deaminated to ammonia in a reaction that converts nicotinamide adenine dinucleotide (NAD) to NADH. For example, alanine is converted to pyruvate and ammonia. The pyruvate is reduced to lactate, and ammonium lactate is excreted into the environment. Unlike lactate from glucose, ammonium lactate is a neutral salt. The common end products in from plaque are ammonium acetate, ammonium propionate, and ammonium butyrate, ammonium salts of short chain fatty acids. For example, glycine is reduced to acetate and ammonia. Cysteine is reduced to propionate, hydrogen sulfide, and ammonia alanine to propionate, water, and ammonia and aspartate to propionate, carbon dioxide, and ammonia. Threonine is reduced to butyrate, water, and ammonia and glutamate is reduced to butyrate, carbon dioxide, and ammonia. Other amino acids are involved in more complicated metabolic reactions that give rise to these short-chain amino acids, sometimes with succinate, another common end product in plaque.

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