Artificial cell-microencapsulated phenylalanine ammonia-lyase.

Phenylalanine ammonia-lyase (PAL) is immobilized in collodion artificial cells. Once technical problems associated with the encapsulation of this enzyme were solved, the enzyme kinetics were compared to PAL in free solution. Microencapsulated PAL has an apparent enzyme activity that is 20% of the activity of enzyme in free solution. The Km for both free and immobilized PAL is 475 microM. The Vm for the microencapsulated PAL is 9 microM/min, whereas that of PAL in free solution is 55 microM/min.