Differentiated structure of synthetic glycogen-like particle by the combined action of glycogen branching enzymes and amylosucrase.

Abstract Glycogen-like particles (GLPs) were built up from sucrose by applying de novo one-pot enzymatic process of amylosucrase (ASase; 6 U·mL−1) and glycogen branching enzymes (GBEs; 0.001 and 0.005 U·mL−1). Due to different chain-length transferring patterns of GBEs, structurally differentiated GLPs were synthesized. Yields of GLPs synthesized at pH 7.0 and 30 °C were improved by increasing the GBE/ASase ratio. Branching degrees of GLPs obviously was increased along with the ratio of GBEs, of which result was directly supported by shortened branch-chain length with greater GBE activity. Long branch chains seemed to play as efficient acceptor molecules to bind newly transferred branch chains especially at lower ratio of GBE/ASase, resulting in greater molecular weight and size of GLP with higher proportion of them. Molecular weight, size, and density of GLPs were ranged from 7.37 × 105 to 1.94 × 108 g·mol−1, from 23.70 to 52.65 nm, and from 7.99 to 374.32 g·mol−1·nm−3, respectively. By increasing GBE/ASase ratio, more compact GLP architecture was fabricated due to increased weight and reduced size with exception of a unique GBE. GLPs were efficiently synthesized by two different glycosyltransferases, and their chemical structures were controllable by source and ratio of GBEs due to their different branch-chain transferring specificity.