Glutamate dehydrogenase structure

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],... 

The same reaction system, immobilized on porous glass, has been used by Winquist et al. (1986) in two reactors combined with an ammonia sensitive iridium metal oxide semiconductor structure in an FLA system. NH3 up to 0.2 mmol/1 could be completely removed in the glutamate dehydrogenase reactor. 

Figure 9.10. The quaternary structure of glutamate dehydrogenase reveals a complex array of subunit interfaces. See color insert.

As the importance of ion-pairs toward protein thermostability has been stressed in many cases, addition or removal of an ion-pair should have significant effects. A clear example is provided by mutagenesis studies of glutamate dehydrogenase from T kodakaraensis KOD1 (Tk-GDH)[361. The GDH from Pyrococcus Juriosus (Pf-GDH) and Tk-GDH are 83% identical in terms of primary structure. However, while Pf GDH displays a half-life of 12 h at 100 C, that of Tk-GDH is 4 h. The three-... 

R. N. Rahman, S. Fujiwara, H. Nakamura, M. Takagi, T. Imanaka, Ion pairs involved in maintaining a thermostable structure of glutamate dehydrogenase from a hyperther-mophilic archaeon, Biochem. Biophys. Res. Commun. 1998, 248(3), 920-926. 

Fig.1. (A) Structure of Omapatrilat (1), an anti hypertensive drug. (B) Enzymatic synthesis of chiral syn-thon for Omapatrilat (1) Reductive amination of sodium 2-keto-6-hydroxyhexanoic acid (3) to (5)-6-hy-droxynorleucine (2) by glutamate dehydrogenase.

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