Aspartate residues dehydrogenases

Figure 1.9 Examples of functionally important intrinsic metal atoms in proteins, (a) The di-iron center of the enzyme ribonucleotide reductase. Two iron atoms form a redox center that produces a free radical in a nearby tyrosine side chain. The iron atoms are bridged by a glutamic acid residue and a negatively charged oxygen atom called a p-oxo bridge. The coordination of the iron atoms is completed by histidine, aspartic acid, and glutamic acid side chains as well as water molecules, (b) The catalytically active zinc atom in the enzyme alcohol dehydrogenase. The zinc atom is coordinated to the protein by one histidine and two cysteine side chains. During catalysis zinc binds an alcohol molecule in a suitable position for hydride transfer to the coenzyme moiety, a nicotinamide, [(a) Adapted from P. Nordlund et al., Nature 345 593-598, 1990.)...

Johnson, A.R., and Dekker, E.E. (1996) Woodward s reagent K inactivation of Escherichia coli L-threo-nine dehydrogenase Increased absorbance at 340-350 nm is due to modification of cysteine and histidine residues, not aspartate or glutamate carboxyl groups. Protein Sci. 5, 382-390. 

Data taken form Craik et al. (1987) for rat trypsin Wilks et al. (1990) for B. stereothermophilus lactate dehydrogenases Muraki et al. (1992) for human lysozyme in which the active site residues refer to E35, D53, W64, D102 and W109 and AGr = -RTIn[(koat/Kra)niutant/ (kcat/Kra)wiidl Stebbins and Kantrowitz (1992) for B. subtilis aspartate transcarbamylase Casal et al. (1987) for yeast triosephosphate isomerase Dupureur et al. (1992) for pancreatic phospholipase Mrabet et al. (1992) for Actinoplanes missouriensis xylose isomerase. 

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