Physical properties and structure of enzymatically synthesized amylopectin analogs

The mechanism of the enzymatic polymerization of amylopectin analogs with phosphorylase b and glycogen branching enzyme is very intriguing. Recently, size exclusion chromatography with multi-detection of enzymatically synthesized amylopectin analogs in combination with MALDI-ToF MS analysis of enzymatically debranched analogs was used to solve parts of the molecular mechanism of analog's enzymatic polymerization. In this work dynamic light scattering (DLS), AFM and cryo-TEM, respectively were used to determine structural characteristics of the same analogs. The results were compared with SEC analyses. The presented analyses in this work fully agreed with the recently made observations and confirmed the changes in the architecture of the synthesized polysaccharide due to the change of enzymatic polymerization mechanism. Furthermore, we showed that the synthetic amylopectin analogs are stable to retrogradation at 4 degrees C if the main side chain length is no longer than 12 glucose units and that they have mostly fluid-like behavior in the form of 20% suspensions.