Culture and bioconversion use of plasmid-harboring strain of immobilized E. coli

Summary Growing Escherichia coli BZ18/pTG 201 cells were immobilized in Kappa-carrageenan gel beads. The bacterial growth after immobilization was studied by cellular counting and by morphological observations with electron microscopy. Kinetic studies of the Catechol 2–3 dioxygenase carried by the plasmid pTG 201 were performed with a packed-bed reactor to show the potential of such a system. High cell densities 1.7×10¹¹ cells/ml) were observed in the cavities of the gel. Due to the difference between the cell density in suspension (8x10⁸ cells/ml) and that within the gel cavities, a reduction of the reactor size and investment cost for processes can be predicted.