β-Glucan phosphorylases in carbohydrate synthesis

Abstract

β-Glucan phosphorylases are carbohydrate-active enzymes that catalyze the reversible degradation of β-linked glucose polymers, with outstanding potential for the biocatalytic bottom-up synthesis of β-glucans as major bioactive compounds. Their preference for sugar phosphates (rather than nucleotide sugars) as donor substrates further underlines their significance for the carbohydrate industry. Presently, they are classified in the glycoside hydrolase families 94, 149, and 161 (www.cazy.org). Since the discovery of β-1,3-oligoglucan phosphorylase in 1963, several other specificities have been reported that differ in linkage type and/or degree of polymerization. Here, we present an overview of the progress that has been made in our understanding of β-glucan and associated β-glucobiose phosphorylases, with a special focus on their application in the synthesis of carbohydrates and related molecules. Key points • Discovery, characteristics, and applications of β-glucan phosphorylases. • β-Glucan phosphorylases in the production of functional carbohydrates.

β-1,3-Glucan synthesis, novel supramolecular self-assembly, characterization and application

“…, 50 mM glucose (acceptor) and 200 mM glucose 1-phosphate (donor). 43,44 Insoluble β-1,3-glucan was produced in all temperatures (Fig. 1b).…”

“…Glycosyl acceptor and donor concentrations employed were typical for reverse reactions with phosphorylases, i.e., 50 mM glucose (acceptor) and 200 mM glucose 1-phosphate (donor). 43,44 Insoluble β-1,3-glucan was produced in all temperatures (Fig. 1b).…”

Exploration of GH94 Sequence Space for Enzyme Discovery Reveals a Novel Glucosylgalactose Phosphorylase Specificity

“…[2] The engineering and application of these enzymes in biotechnological processes have enabled the synthesis of carbohydrates with added value. [3] The diversity of known GPs is rather limited, and it is likely that many enzymes with novel specificities remain to be discovered. [2] Indeed, since the emergence of next-generation sequencing at the beginning of this century, the number of available gene and protein sequences has increased drastically.…”

Insights to improve the activity of glycosyl phosphorylases from Ruminococcus albus 8 with cello-oligosaccharides

“…This microorganism degrades cello-oligosaccharides mainly through phosphorolysis catalyzed by cellobiose phosphorylase (RalCBP; EC 2.4.1.2) and cellodextrin phosphorylase (RalCDP; EC 2.4.1.49) rather than hydrolysis catalyzed by β-glucosidase (Hamura et al, 2012;Sawano et al, 2013). Glycoside phosphorylases belong to the glycoside hydrolase family 94 (GH94) and play an important role in the metabolism of long-chain cellodextrins (Ubiparip et al, 2021). They catalyze a glycoside's reversible phosphorolysis to produce the corresponding sugar 1-phosphate (Eq.…”

“…They have the broadest acceptor and donor substrate specificity of all GH94 enzymes, making them good tools for suitable biocatalytic production of diverse carbohydrates and related molecules. Still, the average degree of polymerization (DP) of cellodextrin produced by CDP ranged from 8 to 10 glucose units, suggesting that these enzymes cannot elongate high DP cellodextrin chains (Ubiparip et al, 2021). This lack of capacity may result from the decrease in cellodextrin solubility as their DP increases, leading to reduced access of the soluble enzyme to the longer substrates.…”