Transferases in Polymer Chemistry - Enzymatic Polymerisation - page 38

Fig. 8 Reactions catalyzed by glycogen phosphorylase ( above ) and glycogen branching enzyme

( below )

Fig. 9 Hybrid structures with amylopectin

branching enzyme is able to transfer short, α -(1 → 4) linked, oligosaccharides from

→

the non-reducing end of starch to an 6) position (see Fig. 8 ) . By combin-

ing the branching enzyme with phosphorylase, it becomes possible to synthesize
branched structures via a one-pot synthesis because phosphorylase will polymerize
linear amylose and the glycogen branching enzyme will introduce the branching
points, which are again extended by phosphorylase.
As shown above, hybrid structures bearing amylose blocks can be synthesized
by covalent attachment of primer recognition units for phosphorylase and subse-
quent enzymatic “grafting from” polymerization. Following the same route, we
are currently synthesizing hybrid materials bearing (hyper)branched polysaccharide
structures (as shown in Fig. 9 ) with the described tandem reaction of two enzymes.
The branched structure, high amount of functional groups, and biocompatibility of
these structures make these architectures suitable for applications in the biomedical
field and in the food industry.

α -(1