Temperature Dependence of the Nitrile Hydratase-Amidase Cascade System

Continuous mns were carried out in a stirred cell ultrafiltration module using the fluoropolymer membrane FS61PP with a nominal molecular weight cut-off of 20kDa. The reactor, loaded with an appropriate amount of resting cells, was fed with a buffered substrate solution by a peristaltic pump with the flow rate set at 

12-14ml/h in most runs or as indicated in the experiments at different t. The stirred cell module was submerged in a thermostated water bath for temperature control ( 0.1 °C). A constant stirrer speed (250rev/min) guaranteed mixing and absence of cell polarization phenomena on the membrane surface. The chemicals used in the runs did not affect the membrane flow characteristics and no rejection of solutes was determined. The permeate was collected by means of an automatic fraction collector, the volume measured, and the samples analyzed every 2 h for reaction product(s) and unreacted substrate. 

Temperature Dependence of the Nitrile Hydratase- midase Cascade System 

The thermal stability of enzymes also has to be investigated in order to characterize the temperature dependence of the reaction kinetics fully. The rate at which 

It is therefore crucial to test the enzyme stabiUty under conditions as close as possible to those encountered during reactor operation. 

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