Glutamate dehydrogenase EC

These enzymes utilize L-glutamate and the 4-pro-S position of the coenzyme [38,39]. Crystals have been obtained in many cases (summarized in [95]). Those from mammalian liver were not suitable for structure determination. For example, crystals of the rat liver enzyme had a large unit cell, and were unstable in the X-ray beam [96], The NADP-dependent enzyme from Neurospora crassa is smaller than the mammalian enzyme, and less complicated with respect to allosteric and aggregation effects. Nevertheless, carefully grown crystals did not provide X-ray diffraction patterns favourable for structure determination (A.C.T. North, personal communication). At present, best hopes reside in crystals of the yellowfin tuna liver enzyme [97]. 

In primary structure, the NADP-dependent N. crassa enzyme shows clear but limited homology with the vertebrate glutamate dehydrogenases in the N-terminal two-thirds of the chain [98]. Interestingly, the NAD-dependent enzyme of N. crassa has a much larger subunit, with an apparently dissimilar sequence [99], 

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Very low concentrations of substrates may be assayed by recycling the test substrate for an appreciable but definite period of time and measuring the amount of product formed. The coenzyme NADPH, for instance, may be assayed using the two enzymes glutamate dehydrogenase (EC 1.4.1.3) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49) ... 

Glutamate dehydrogenase [EC 1.4.1.2] catalyzes the reaction of L-glutamate with NAD+ and water to produce a-ketoglutarate (or, 2-oxoglutarate), ammonia, and NADH. 

Glutamate dehydrogenase (EC 1.4.1.3 L-glutamate NAD(P) oxidoreductase, deaminating GLD) is a mitochondrial enzyme found mainly in the liver, heart muscle, and kidneys, but small amounts occur in other tissue, including brain and skeletal muscle tissue, and in leukocytes. 

Glutamate dehydrogenase (EC 1.4.1.3) has been used for glutamate determination (Schubert et al., 1986b) as well as for quantitative removal of ammonia (Mascini et al., 1985a) (see Section 3.2). 

L-Glutamate dehydrogenases (EC 1.4.1.2-4) catalyze the interconversion of a-ketoglutarate and L-glutamic acid ... 

Amlnation introduction of an amino group ( NH2) into an organic compound. This may be accomplished by reductive A. or by Transamination (see). Reductive A. requires a reduced pyridine nucleotide as a reducing agent, e.g. the most common reductive A. of 2-oxoglutarate by L-glutamate dehydrogenase (EC 1.4.1.4) requires NADPH. 

In plants, molds and bacteria, A. a. into the amino group of glutamate is also possible by NADPH-de-pendent glutamate dehydrogenase (EC 1.4.1.3) the enzyme is most effective when ammonium salts are available directly from the environment in relatively... 

The matrix contains all the enzymes of the TCA-cy-cle (see), with the exception of succinate dehydrogenase, Also present are glutamate dehydrogenase (EC... 

A major class of enzymes that catalyze oxidation-reduction reactions. This class includes dehydrogenases, reductases, oxygenases, peroxidases, and a few synthases. Examples include alcohol dehydrogenase (EC 1.1.1.1), aldehyde oxidase (EC 1.2.3.1), orotate reductase (EC 1.3.1.14), glutamate synthase (EC 1.4.1.14), NAD(P) transhydrogenase (EC 1.6.1.1), and glutathione peroxidase (EC 1.11.1.9). 

Figure 6.3. GABA shunt as an alternative to a-ketoglutarate dehydrogenase in the citric acid cycle. 2-Oxoglutarate dehydrogenase, EC 1.2.4.2 glutamate decarboxylase, EC 4.1.1.15 GABA aminotransferase, EC 2.6.1.19 and succinic semialdehyde dehydrogenase, ECl.2.1.16.

EC 1.4.1.2 Glutamate dehydrogenase ketoglutarate+nadred+ammonia=glutamate+nadox+h2o... 

Deutsche Gesellschaft fiir Klinische Chemie. Proposal of standard methods for the determination of enzyme catalytic concentrations in serum and plasma at 37°C. III. Glutamate dehydrogenase (L-glutamate NAD(P) oxidoreductase (deaminating), EC 1.4.1.3). Eur J Clin Chem CUn Biochem 1992 30 493-502. 

Creatinine deaminase (EC 3.5.4.21 creatinine imino-hydrolase) catalyzes the conversion of creatinine to N-methylhydantoin and ammonia. Early methods concentrated on tlie detection of ammonia using either glutamate dehydrogenase or the Berthelot reaction. An alternative approach involves the enzyme N-methylhydantoin amido-hydrolase (Figure 24-l,D). ... 

Glutamate dehydrogenase (GDH, oxido-reductase, EC 1.4.1.3) 2-oxoglutarate + NH4+ + NADH or glutamate + NAD Moderately specific... 

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