Nitrilase prokaryotic nitrilases

On the basis of sequence data and biochemical characterization, this chapter wiU compare the structure and enzymatic properties of nitrilases from filamentous fungi with those of prokaryotic and plant nitrilases as well as other related enzymes like cyanide hydratases and cyanide dihydratases. The biotechnological potential of fungal nitrilases will be evaluated. 

Table 14.1 Subunit and holoenzyme molecular masses of nitrilases from filamentous fungi comparison with selected prokaryotic nitrilases, cyanide hydratases and cyanide dihydratase.

Recently, the spectrum of known nitrilases was significantly enlarged by a screening of 290 prokaryotic nifrilase genes [20]. Of these, 163 were expressed and 125 protein products proved to exhibit nitrilase activities for at least some of the 25 nitriles tested. For instance, nitrilases from Sphingomoms wittichii and Syntrophobacter fumaroxidans were optimal catalysis for the synthesis of (R)-4-methoxy-4-oxo-3-phenylbutanoic acid and 3-oxocyclopenfanecarboxylic acid (building blocks), respectively. 

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