Tyrosine decarboxylase

Pyridoxamine phosphate serves as a coenzyme of transaminases, e.g., lysyl oxidase (collagen biosynthesis), serine hydroxymethyl transferase (Cl-metabolism), S-aminolevulinate synthase (porphyrin biosynthesis), glycogen phosphoiylase (mobilization of glycogen), aspartate aminotransferase (transamination), alanine aminotransferase (transamination), kynureninase (biosynthesis of niacin), glutamate decarboxylase (biosynthesis of GABA), tyrosine decarboxylase (biosynthesis of tyramine), serine dehydratase ((3-elimination), cystathionine 3-synthase (metabolism of methionine), and cystathionine y-lyase (y-elimination). 

Owing to the fully reversible equilibrium nature of the aldol addition process, enzymes with low diastereoselectivity will typically lead to a thermodynamically controlled mixture of erythro/threo-isomers that are difficult to separate. The thermodynamic origin of poor threo/erythro selectivity has most recently been turned to an asset by the design of a diastereoselective dynamic kinetic resolution process by coupling of L-ThrA and a diastereoselective L-tyrosine decarboxylase (Figure 10.47)... 

A classical approach to driving the unfavorable equilibrium of an enzymatic process is to couple it to another, irreversible enzymatic process. Griengl and coworkers have applied this concept to asymmetric synthesis of 1,2-amino alcohols with a threonine aldolase [24] (Figure 6.7). While the equilibrium in threonine aldolase reactions typically does not favor the synthetic direction, and the bond formation leads to nearly equal amounts of two diastereomers, coupling the aldolase reaction with a selective tyrosine decarboxylase leads to irreversible formation of aryl amino alcohols in reasonable enantiomeric excess via a dynamic kinetic asymmetric transformation. A one-pot, two-enzyme asymmetric synthesis of amino alcohols, including noradrenaline and octopamine, from readily available starting materials was developed [25]. 

The leucocyte method estimates pyridoxal phosphate in isolated leucocytes it is based on a coenzyme-catalyzed tyrosine decarboxylase system from S. faecalis (B32). Enough data are not yet on hand to evaluate this method. The determination of circulating or available vitamin Ba should offer a more direct approach. 

Voigt, M.N. and Eitenmiller, R.R. (1978). Role of histidine and tyrosine decarboxylases and mono diamine oxidases in amine build-up in cheese, J. Food Prot., 41, 182. 

Researchers at the University of Graz, in collaboration with scientists from DSM, have developed an elegant and novel approach to the synthesis of P-amino alcohols using two different enzymes in one pot (Scheme 2.35). For example, a threonine aldolase-catalyzed reaction was initially used, under reversible conditions, to prepare L-70 from glycine 69 and benzaldehyde 68. L-70 was then converted to (R)-71 by an irreversible decarboxylation catalyzed by L-tyrosine decarboxylase. In a second example, D/L-syn-70 was converted to (R)-71 using the two enzymes shown combined with a D-threonine aldolase in greater than 99% e. e. and 67% yield ]37, 38]. 

Scheme 2.35 Combined use of threonine aldolase and L-tyrosine decarboxylase.

L-Tyrosine decarboxylase (2 mg/ml, 0.8 ml) in 100 mM sodium acetate buffer (pH 5.5) was treated with canaline as indicated for 30 min. A unit of tyrosine decarboxylase activity is that amount of enzyme forming 1 umol CO /min. See original for additional details. 

Morphine and codeine biosynthesis (Samuelsson, 1999 Herbert et al., 2000 Novak et al., 2000) Studies on the biosynthesis of morphine have been carried out mainly on cell cultures mainly of Coptis japonica and species of Thalictrum. Two enzymes (tyrosine decarboxylase and phenolase) catalyze the formation of dopamine from one molecule tyrosine. Dopamine is also the key intermediate in the biosynthesis of mescaline. 

At about the same time, Gunsalus and coworkers noticed that the activity of tyrosine decarboxylase produced by lactic acid bacteria was unusually low when the medium was deficient in pyridoxine. Addition of pyridoxal plus ATP increased the decarboxylase activity of cell extracts.146 PLP was synthesized and was found to be the essential coenzyme for this and a variety of other enzymes.147... 

One of the earliest published attempts to create antibodies with catalytic activity had as its goal the generation of a transaminase. Raso and Stollar prepared V-(5-phosphopyridoxyl)-3 -amino-L-tyrosine 154 as a mimic of the Schiff s base intermediate that is formed during the pyridoxal-dependent transamination of tyrosine and showed that it was a site-directed inhibitor of the enzymes tyrosine transaminase and tyrosine decarboxylase.132 Partially purified polyclonal antibodies, elicited against y-globulin conjugates of the hapten, recognized both the... 

MARQUES, I.A., BRODELRJS, P.E., Elicitor-induced L-tyrosine decarboxylase from plant cell suspension cultures I. Induction and purification. Plant Physiol., 1988,88, 47-51. 

Tyrosine decarboxylase (EC.4.1.1.25), responsible for the production of tyramine from tyrosine, was first investigated in a wine lactic acid bacteria by... 

Moreno-Arribas and Lonvaud-Funel (1999). Moreno-Arribas et al. (2000) isolated and identified a number of tyramine-producing lactic acid bacteria in wine that had undergone malolactic fermentation all belonging to the lactobacilli. Tyrosine decarboxylase was then purified (Moreno-Arribas and Lonvaud-Funel 2001) and the corresponding gene was purified and sequenced (Lucas and Lonvaud-Funel 2002 Lucas et al. 2003). As far as the literature suggests, no tyramine-producing 0. oeni strain has yet been reported, with the exception of one strain (O. oeni DSM 2025) that was shown to be able to produce tyramine in a laboratory medium (Choudhury etal. 1990). 

Coton, M., Coton, E., Lucas, P. Lonvaud, A. (2004). Identification of the gene encoding a putative tyrosine decarboxylase of Camobacterium divergens 508. Development of molecular tools for the detection of tyramine-producing bacteria. Eood Microbiol, 21, 125-130. 

Lucas, P. Lonvaud-Funel, A. (2002). Purification and partial gene sequence of the tyrosine decarboxylase of Lactobacillus brevis lOEB 9809. FEMS Microbiol. Lett., 211, 85-89. 

Keywords chemotaxonomy patchy distribution biosynthesis genes horizontal gene transfer endophytes evolution tryptophan decarboxylase tyrosine decarboxylase phenylalanine ammonia-lyase chalcone synthase strictosidine synthase berberine bridge enzyme codeine reductase... 

Figure 7.16 Phylogenetic relationships in key enzymes of pathways leading to SM, based on amino acid sequences, (a) Ornithine decarboxylase (ODC). (b) Tyrosine decarboxylase (TyrDC). (c) Tryptophan decarboxylase (TDC). (d) Phenylalanine ammonia-lyase (PAL). Numbers at nodes are bootstrap values.

Tyrosine decarboxylase, which is a key enzyme in the biosynthesis of isoquinoline alkaloids in plants, also occurs in all kingdoms of life (Fig. 7.16b, Table 7.3). The enz)mie catalyses the decarboxylation of tyrosine... 

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