Uncommon Glycosidases for the Enzymatic Preparation of Glycosides

Abstract

Most of the reports in literature dedicated to the use of glycosyl hydrolases for the preparation of glycosides are about gluco- (α- and β-form) and galacto-sidase (β-form), reflecting the high-availability of both anomers of glucosides and of β-galactosides and their wide-ranging applications. Hence, the idea of this review was to analyze the literature focusing on hardly-mentioned natural and engineered glycosyl hydrolases. Their performances in the synthetic mode and natural hydrolytic potential are examined. Both the choice of articles and their discussion are from a biomolecular and a biotechnological perspective of the biocatalytic process, shedding light on new applicative ideas and on the assortment of biomolecular diversity. The hope is to elicit new interest for the development of biocatalysis and to gather attention of biocatalyst practitioners for glycosynthesis.

Human milk and mucosal lacto- and galacto-N-biose synthesis by transgalactosylation and their prebiotic potential in Lactobacillus species

“…These are major building blocks of oligosaccharides present in human milk and gastrointestinal mucosa. The transgalactosylation efficiency of GnbG is remarkably high compared with the efficiency of other glycosidases, which usually is moderately ranged from 20 to 40 % (Schmaltz et al 2011;Trincone 2015). Indeed, LNB and GNB have been previously Fig.…”

Forty years of study on the thermostable β‐glycosidase fromS. solfataricus: Production, biochemical characterization and biotechnological applications

“…Some simple unsaturated alcohols were glycosylated with yields in glycosides higher than those obtained using mesophilic counterparts glycosidases. Modulating the amount of acceptors, a reasonable amount of products could be obtained by adding different aliquots of donor at time intervals [55]. The reaction stereochemistry was described by a covalent intermediate between the glycosidic group with the catalytic residue in the active site of enzyme, and subsequent transfer to a nucleophile other than water (Fig.…”

“…The reaction stereochemistry was described by a covalent intermediate between the glycosidic group with the catalytic residue in the active site of enzyme, and subsequent transfer to a nucleophile other than water (Fig. 1B) [22,24,55]. The Sβgly stability to temperature and organic solvents [25] allowed the use of high molar excess of alcohols (high content of organics) and high reaction temperatures, obtaining high yields and absolute chemoselectivity and stereoselectivity (100% pure anomer), biotechnologically relevant for the synthesis of derivatized glycosides [55].…”

“…Considering that Sβgly did not exhibit allosteric behavior [21], the availability of both active tetrameric and dimeric forms of the enzyme makes possible to study the relationships between oligomerization and physicochemical properties other than allosteric regulation, also from an evolutionary point of view. The Sβgly stability to organic solvents, such as alcohols, has been widely demonstrated in the transglycosylation reactions, where aliphatic and aromatic hydroxyl groups were used as nucleophilic acceptors [13,55].…”

Metabolismo y síntesis de oligosacáridos de la leche humana mediante la utilización de enzimas glicosil hidrolasas de Lactobacillus casei

“…En este trabajo se ha descrito la síntesis de esos disacáridos mediante la transgalactosidación catalizada por la fosfo--galactosidasa GnbG, obteniendo un rendimiento aproximado del 70%. La eficiencia de esta reacción es especialmente alta si la comparamos con la eficiencia de otras glicosidasas, con las cuales se han obtenido rendimientos de entre el 20 y el 40% (Schmaltz et al, 2011;Trincone, 2015). De hecho, LNB y GNB han sido previamente sintetizadas en reacciones de transglicosidación con la β-galactosidasa BgaC de Bacillus circulans, pero con rendimientos bajos (12.2 y 10.1% para LNB y GNB, respectivamente) (Fujimoto et al, 1998).…”