Dual Decomposition Pathways for L-Aspartic acid on Ni(100)

The radiolysis of the isomers L-, D- and DL- of the aspartic acid, in solid polycrystalline state, was investigated at room temperature. The analysis of their ESR spectra indicated the formation of at least two radicalic entities. The radical, identified as R3, resulting from the deamination of the acid, exhibits the highest concentration and thermal resistance. Possible mechanisms of formation of three radical species are suggested, based also on literature data. The kinetics of the disappearance of radical R3 indicated a complex mechanism. Three possible variants were suggested for this mechanism.

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Enzymatic Synthesis of 15N-L-aspartic Acid Using Recombinant Aspartase from Escherichia Coli K12

Revista de Chimie ◽

10.37358/rc.08.11.2004 ◽

2008 ◽

Vol 59 (11) ◽

Cited By ~ 1

Author(s):

Iulia Lupan ◽

Sergiu Chira ◽

Maria Chiriac ◽

Nicolae Palibroda ◽

Octavian Popescu

Keyword(s):

Amino Acids ◽

Aspartic Acid ◽

Enzymatic Synthesis ◽

Large Scale ◽

Recombinant Dna ◽

Industrial Enzymes ◽

Recombinant Dna Technology ◽

Bacterial Fermentation ◽

Natural Protein ◽

Novel Method

Amino acids are obtained by bacterial fermentation, extraction from natural protein or enzymatic synthesis from specific substrates. With the introduction of recombinant DNA technology, it has become possible to apply more rational approaches to enzymatic synthesis of amino acids. Aspartase (L-aspartate ammonia-lyase) catalyzes the reversible deamination of L-aspartic acid to yield fumaric acid and ammonia. It is one of the most important industrial enzymes used to produce L-aspartic acid on a large scale. Here we described a novel method for [15N] L-aspartic synthesis from fumarate and ammonia (15NH4Cl) using a recombinant aspartase.

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Bioavailability of Aspartic Acid Chelated Iron on Iron-deficient Rats

Journal of the Korean Society of Food Science and Nutrition ◽

10.3746/jkfn.2011.40.12.1720 ◽

2011 ◽

Vol 40 (12) ◽

pp. 1720-1725

Author(s):

Myoung-Gyu Park ◽

Tae-Yul Ha ◽

Kwang-Soon Shin

Keyword(s):

Aspartic Acid ◽

Iron Deficient ◽

Chelated Iron

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Improved and Large-Scale Synthesis of N-methyl-D-aspartic Acid

Current Organic Synthesis ◽

10.2174/1570179411666141113215036 ◽

2015 ◽

Vol 12 (2) ◽

pp. 197-201 ◽

Cited By ~ 3

Author(s):

Liang Xi ◽

Di Wu ◽

Hong-You Zhu ◽

Cong-Hai Zhang ◽

Yi Jin ◽

...

Keyword(s):

Aspartic Acid ◽

Large Scale ◽

Large Scale Synthesis

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Design of a continuous flow immobilized-cell reactor for biosynthetical production of L-aspartic acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19852122 ◽

1985 ◽

Vol 50 (10) ◽

pp. 2122-2133 ◽

Cited By ~ 2

Author(s):

Jindřich Zahradník ◽

Marie Fialová ◽

Jan Škoda ◽

Helena Škodová

Keyword(s):

Aspartic Acid ◽

Continuous Flow ◽

Immobilized Cells ◽

Scale Up ◽

Fixed Bed ◽

Packed Bed ◽

Fixed Bed Reactor ◽

Experimental Program ◽

Design Parameters ◽

Immobilized Cell

An experimental study was carried out aimed at establishing a data base for an optimum design of a continuous flow fixed-bed reactor for biotransformation of ammonium fumarate to L-aspartic acid catalyzed by immobilized cells of the strain Escherichia alcalescens dispar group. The experimental program included studies of the effect of reactor geometry, catalytic particle size, and packed bed arrangement on reactor hydrodynamics and on the rate of substrate conversion. An expression for the effective reaction rate was derived including the effect of mass transfer and conditions of the safe conversion-data scale-up were defined. Suggestions for the design of a pilot plant reactor (100 t/year) were formulated and decisive design parameters of such reactor were estimated for several variants of problem formulation.

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Post-proline endopeptidase, further characterization of the enzyme from pig kidneys

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19841846 ◽

1984 ◽

Vol 49 (8) ◽

pp. 1846-1853 ◽

Cited By ~ 4

Author(s):

Karel Hauzer ◽

Tomislav Barth ◽

Linda Servítová ◽

Karel Jošt

Keyword(s):

Amino Acids ◽

Aspartic Acid ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Relative Molecular Mass ◽

Enzyme Molecule ◽

Thiol Compounds ◽

Modified Method ◽

N Terminus

A post-proline endopeptidase (EC 3.4.21.26) was isolated from pig kidneys using a modified method described earlier. The enzyme was further purified by ion exchange chromatography on DEAE-Sephacel. The final product contained about 95% of post-proline endopeptidase. The enzyme molecule consisted of one peptide chain with a relative molecular mass of 65 600 to 70 000, containing a large proportion of acidic and alifatic amino acids (glutamic acid, aspartic acid and leucine) and the N-terminus was formed by aspartic acid or asparagine. In order to prevent losses of enzyme activity, thiol compounds has to be added.

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