Microbiological synthesis of L-3,4-dihydroxyphenylalanine

Sih, Charles J.; Foss, Paul; Rosazza, John P. N.; Lemberger, Michael

doi:10.1021/ja01050a061

Cited by 31 publications

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“…This work substantiates the findings of Haneda et al (1973) and Raju et al (1993). Sih et al (1969) obtained maximum production of L-DOPA at pH 5 of the medium while Andrews (2002) found maximum production of L-DOPA in a medium close to neutral (pH 6.5).…”

Section: Resultsmentioning

confidence: 94%

“…This study is in good agreement with that of Raju et al (1993) who also found glucose to be the best carbon source to bring about optimal production of mycelia and tyrosinases. In other enzyme systems, disaccharides or higher molecular weight substrates have been found to be the best supporters of enzyme production (Sih et al 1969;Bubbico et al 2001;Andrews 2002). It can be concluded that tyrosinase is a constitutive enzyme and mutagensis gave rise to a mutant, which was further altered with respect to production of tyrosinases in the presence of glucose.…”

Section: Resultsmentioning

confidence: 99%

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Kinetic basis of celite (CM 2:1) addition on the biosynthesis of 3,4-dihydroxyphenyl-l-alanine (l-DOPA) by Aspergillus oryzae ME2 using l-tyrosine as a basal substrate

Ali

Haq

2005

World J Microbiol Biotechnol

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Celite is a unique variety of 2:1 clay mineral and is referred to as hydrous mica because it is believed to be the weathering product of mica. The present study describe the effect of celite on microbiological conversion of L-tyrosine to 3,4-dihydroxyphenyl-L-alanine (L-DOPA) by Aspergillus oryzae ME 2 . At optimum pH (pH o =6), and temperature (t=30°C), 100% sugars were utilized for cell mass formation. Mould mycelium was used for biochemical conversion of L-tyrosine to L-DOPA because tyrosinases, b-carboxylases and tyrosine hydroxylases are intracellular enzymes. The maximum conversion of L-tyrosine to L-DOPA (0.428 mg/ml) was achieved after 60 min of reaction. To further enhance the production of L-DOPA, different concentration of celite were added to the reaction mixture. Best results were observed when the concentration of celite was 3.5 lM (1.686 mg L-DOPA produced/ml with 1.525 mg L-tyrosine consumed/ml). There was up to 3-fold enhancement in the product formation rate. This enhancement is the highest so far reported. Celite not only increased enzyme activity but also enhanced the permeability of the cell membrane to facilitate the secretion of enzymes in to the reaction broth. The comparison of kinetic parameters showed the ability of the mutant to yield L-DOPA (i.e., Y p/x 7.360±0.04 mg/mg). When the culture grown on various celite levels was monitored for Q p , Q s and q p , there was significant enhancement (P<0.025) in these variables over the control, which indicates that the study can be commercially applicable (HS, LSD 0.456).

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Section: Resultsmentioning

confidence: 94%

Section: Resultsmentioning

confidence: 99%

Kinetic basis of celite (CM 2:1) addition on the biosynthesis of 3,4-dihydroxyphenyl-l-alanine (l-DOPA) by Aspergillus oryzae ME2 using l-tyrosine as a basal substrate

Ali

Haq

2005

World J Microbiol Biotechnol

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“…Predictive systems of varying degrees of sophistication have been developed for a number of enzymes, including proteases (2a), mono-oxygenases (7,8), and some alcohol dehydrogenases (2a, 3 , 4 , 9 ) . For HLADH, the diamond lattice section approach devised by Prelog ( 3 , and subsequently refined ( 2 a , 4 ) , has been very successful for interpreting the steric course of catalyses of cyclohexane and decalin substrates.…”

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confidence: 99%

A new cubic-space section model for predicting the specificity of horse liver alcohol dehydrogenase-catalyzed oxidoreductions

Jones¹,

Jakovac²

1982

Can. J. Chem.

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A new active site model for predicting and interpreting the stiuctural-and stereospecificity of horse liver alcohol dehydrogenase-catalyzed oxidations and reductions has been formulated from the specificity, X-ray, and kinetic data now available. The new model is based on a cubic-space system and is convenient and easy to use. The model is completely reliable and permits HLADH specificity towards all of its currently known substrates to be predicted with confidence. Its application is illustrated by analyses of representative examples of major substrate types.J. BRYAN JONES et IGNAC J. JAKOVAC. Can. J. Chem. 60, 19 (1982) A partir des donnees de specicite, de diffraction de rayons X et de cinetique disponibles. on a elabore un nouveau modele de site actif pour predire et interpreter la structure et la stereospecifite des oxydations et des reductions catalysee par la deshydrogenase de l'alcool du foie de cheval (DHAFC). Le nouveau modele est fonde sur un systeme d'espace cubique et est d'emploi facile. Le modele est completement fiable et permet de predire en toute confiance la specifite de la DHAFC envers tous ses substrats connus. On illustre son utilisation par I'analyse d'exemples representatifs des principaux types de substrats.[Traduit par le journal]The asymmetric synthetic opportunities provided by the chiral catalytic properties of enzymes are becoming increasingly recognized (2a,b). Alcohol dehydrogenases, which catalyze oxidoreductions of the type depicted in reaction are among the most useful enzymes for organic synthetic purposes, with the commercially available enzyme from horse liver the best documented.HLADH is an extremely versatile alcohol dehydrogenase, capable of effecting highly stereospecific oxidoreductions on a broad structural range of aldehyde, ketone, and alcohol substrates (2-6).In order for any enzyme to become widely adopted as a practical synthetic catalyst, it is essential that a reliable active site model be available for predicting the structural-and stereospecificity of the enzyme towards both known and potential substrate structures. Predictive systems of varying degrees of sophistication have been developed for a number of enzymes, including proteases (2a), mono-oxygenases (7, 8), and some alcohol dehydrogenases (2a, 3 , 4 , 9 ) . For HLADH, the diamond lattice section approach devised by Prelog ( 3 , and subsequently refined ( 2 a , 4 ) , has been very successful for interpreting the steric course of catalyses of cyclohexane and decalin substrates. However, for many of the other types of cyclic structures now known to be substrates ( 2 ) , stereochemical predictions based on diamond lattice analyses have become increasingly subjective and ~n c e r t a i n .~ It is clear that, after serving as a valuable active site model for nearly twenty years, the diamond lattice section has become totally inadequate for interpreting the stereochemical course of HLADH-catalyzed oxidoreductions of many of the recently identified, and still expanding, range of substrate structures (2, 6b)....

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“…However, in microorganisms tyrosinase activity is generally very weak and L-tyrosine and L-DOPA are rapidly decomposed to other metabolites. Thus stoichiometric formation of L-DOPA from L-tyrosine is difficult to achieve (25).…”

Section: Introductionmentioning

confidence: 99%

Mutation of Aspergillus oryzae for improved production of 3, 4-dihydroxy phenyl-L-alanine (L-DOPA) from L-tyrosine

Haq

Ali

2006

Braz. J. Microbiol.

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Aspergillus oryzae mutant strain UV-7 was further improved for the production of L-DOPA from L-tyrosine using chemical mutation. Different putative mutant strains of organism were tested for the production of L-DOPA in submerged fermentation. Among these putative mutant strains, mutant designated SI-12 gave maximum production of L-DOPA (300 mg L-DOPA.g -1 cells). The production of L-DOPA from different carbon source solutions (So= 30 g.l -1 ) by mutant culture was investigated at different nitrogen sources, initial pH and temperature values. At optimum pH (pHo= 5.0), and temperature (t=30ºC), 100% sugars were utilized for production and cell mass formation, corresponding to final L-DOPA product yield of 150 mg.g -1 substrate utilized, and maximum volumetric and specific productivities of 125 mg.l , respectively. There was up to 3-fold enhancement in product formation rate. This enhancement is the highest reported in literature. To explain the kinetic mechanism of L-DOPA formation and thermal inactivation of tyrosinase, the thermodynamic parameters were determined with the application of Arrhenius model: activation enthalpy and entropy for product formation, in case of mutant derivative, were 40 k j/mol and 0.076 k j/mol. K for L-DOPA production and 116 k j/mol and 0.590 k j/mol. K for thermal inactivation, respectively. The respective values for product formation were lower while those for product deactivation were higher than the respective values for the parental culture. Therefore, the mutant strain was thermodynamically more resistant to thermal denaturation.

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Microbiological synthesis of L-3,4-dihydroxyphenylalanine

Cited by 31 publications

References 0 publications

Kinetic basis of celite (CM 2:1) addition on the biosynthesis of 3,4-dihydroxyphenyl-l-alanine (l-DOPA) by Aspergillus oryzae ME2 using l-tyrosine as a basal substrate

Kinetic basis of celite (CM 2:1) addition on the biosynthesis of 3,4-dihydroxyphenyl-l-alanine (l-DOPA) by Aspergillus oryzae ME2 using l-tyrosine as a basal substrate

A new cubic-space section model for predicting the specificity of horse liver alcohol dehydrogenase-catalyzed oxidoreductions

Mutation of Aspergillus oryzae for improved production of 3, 4-dihydroxy phenyl-L-alanine (L-DOPA) from L-tyrosine

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