cells ofStreptomyces lydicusfor the continuous production of PLD in an air-lift
reactor.
The synthesis of polymers with a wide variety of properties offers the opportunity
to prepare supports adapted to the special requirements of a given biocatalyst. Poly-
acrylate, polyamide, polystyrene, etc. are polymers often applied for enzyme immo-
bilization by physical or chemical binding. Co-polymers of methacrylamide with
N,N’-methylene-bis-acrylamide and allylglycidyl ether, or those prepared from vi-
nylacetate and divinylethylene urea, both of which are activated by epoxy groups
(Table 2; Figure 4) have been successfully used for the direct covalent binding
of industrially important enzymes such as penicillin G amidase (Burg et al.,
1988; Kolarz et al., 1990) and have found widespread application in immobilization
practices.
To summarize, a carrier should have the following properties: a hydrophilic sur-
face if the reaction is to be carried out in aqueous solution; functional groups for
270 13 Preparation and Application of Immobilized Phospholipases
Figure 3. Scanning electron micrograph of the surface of a porous glass bead TRISOPERL (length of
bar: 500 nm). The surface is modified with active groups for covalent binding of biocatalysts. (Illustration
courtesy of Schuller GmbH, Germany.)
Figure 4. A scheme of the chemical structure of Eupergit (Ro ̈hm), a porous co-polymer ofN,N’-me-
thylene-bis-(methacrylamide), glycidyl methacrylate, allyl glycidyl ether, and methacrylamide with oxi-
rane groups for covalent enzyme coupling.