A Novel Thermo-Alkaline Stable GDSL/SGNH Esterase with Broad Substrate Specificity from a Deep-Sea Pseudomonas sp.

Marine environments harbor a plethora of microorganisms that represent a valuable source of new biomolecules of biotechnological interest. In particular, enzymes from marine bacteria exhibit unique properties due to their high catalytic activity under various stressful and fluctuating conditions, such as temperature, pH, and salinity, fluctuations which are common during several industrial processes. In this study, we report a new esterase (EstGoM) from a marine Pseudomonas sp.

Deep Eutectic Solvents as New Reaction Media to Produce Alkyl-Glycosides Using Alpha-Amylase from .

Deep Eutectic Solvents (DES) were investigated as new reaction media for the synthesis of alkyl glycosides catalyzed by the thermostable α-amylase from Amy A. The enzyme was almost completely deactivated when assayed in a series of pure DES, but as cosolvents, DES containing alcohols, sugars, and amides as hydrogen-bond donors (HBD) performed best. A choline chloride:urea based DES was further characterized for the alcoholysis reaction using methanol as a nucleophile.

Frucooligosaccharides purification: Complexing simple sugars with phenylboronic acid.

Prebiotic fructooligosaccharides (FOS) are currently obtained by enzymatic reaction with fructosyltransferases (FTFs) using sucrose as both donor and acceptor. In these reactions glucose results as the most abundant by-product, arising from each fructosyl transfer event and, together with fructose, because of the inherent hydrolytic activity of the FTFs. As FOS are mainly used as prebiotic in nutraceutical foods, the reduction or total elimination of monosaccharides is required.

One-Pot Lipase-Catalyzed Enantioselective Synthesis of (R)-(-)-N-Benzyl-3-(benzylamino)butanamide: The Effect of Solvent Polarity on Enantioselectivity.

The use of the solvent engineering has been applied for controlling the resolution of lipase-catalyzed synthesis of β-aminoacids via Michael addition reactions. The strategy consisted of the thermodynamic control of products at equilibrium using the lipase CalB as a catalyst. The enzymatic chemo- and enantioselective synthesis of ()-(-)--benzyl-3-(benzylamino)butanamide is reported, showing the influence of the solvent on the chemoselectivity of the -Michael addition and the subsequent kinetic resolution of the Michael adduct; both processes are catalyzed by CalB and both are influenced by the nature of the solvent medium.

A novel two-step enzymatic synthesis of blastose, a β-d-fructofuranosyl-(2↔6)-d-glucopyranose sucrose analogue.

Blastose, a natural disaccharide found in honey, is usually found as a byproduct of fructo-oligosaccharide synthesis from sucrose with fructosyltransferases. In this study, we describe a novel two-step biosynthetic route to obtain blastose, designed from a detailed observation of B. subtilis levansucrase (SacB) acceptor structural requirements for fructosylation.

The first description of a hormone-sensitive lipase from a basidiomycete: Structural insights and biochemical characterization revealed Bjerkandera adusta BaEstB as a novel esterase.

The heterologous expression and characterization of a Hormone-Sensitive Lipases (HSL) esterase (BaEstB) from the Basidiomycete fungus Bjerkandera adusta is reported for the first time. According to structural analysis, amino acid similarities and conservation of particular motifs, it was established that this enzyme belongs to the (HSL) family. The cDNA sequence consisted of 969 nucleotides, while the gene comprised 1133, including three introns of 57, 50, and 57 nucleotides.

Acceptor-induced modification of regioselectivity in CGTase-catalyzed glycosylations of p-nitrophenyl-glucopyranosides.

Cyclodextrin glycosyltransferases (CGTase) are reported to selectively catalyze α(1 → 4)-glycosyl transfer reactions besides showing low hydrolytic activity. Here, the effect of the anomeric configuration of the glycosyl acceptor on the regioselectivity of CGTase catalyzed glycosylations was investigated. For this purpose, the α and β anomers of p-nitrophenyl-D-glucopyranoside were used as glycosyl acceptors, Bacillus macerans and Thermoanaerobacter sp.

Regioselective glucosylation of inositols catalyzed by Thermoanaerobacter sp. CGTase.

Monoglucosylated products of L-chiro-, D-chiro-, muco-, and allo-inositol were synthesized by regioselective α-D-glucosylation with cyclodextrin glucosyl transferase from Thermoanaerobacter sp. after hydrolysis of by products with Aspergillus niger glucoamylase. While the reactions carried out with D-chiro-, muco-, and allo-inositol resulted in the regioselective formation of monoglucosylated products, two products were obtained in the reaction with L-chiro-inositol.

Thermodynamical methods for the optimization of lipase-catalyzed reactions.

A basic insight on different thermodynamical strategies reported for the optimization of lipase-catalyzed reactions is presented. The significance of selecting the appropriate reaction media in order to enhance selectivity and operational stability of enzymes is discussed. From this analysis, the importance of developing thermodynamic strategies for controlling both the reaction kinetics and equilibrium is emphasized.

Phenylpropanoid glycoside analogues: enzymatic synthesis, antioxidant activity and theoretical study of their free radical scavenger mechanism.

Phenylpropanoid glycosides (PPGs) are natural compounds present in several medicinal plants that have high antioxidant power and diverse biological activities. Because of their low content in plants (less than 5% w/w), several chemical synthetic routes to produce PPGs have been developed, but their synthesis is a time consuming process and the achieved yields are often low. In this study, an alternative and efficient two-step biosynthetic route to obtain natural PPG analogues is reported for the first time.

Enzymatic synthesis of capsaicin analogs and their effect on the T-type Ca2+ channels.

Capsaicin (Cap) and its analogs (CAPanalogs) have diverse effects in sensory neurons including analgesia, implying they modulate other cellular targets besides the TRPV1 Cap receptor. Since Cap and CAPanalogs are not largely available and their chemical synthesis is cumbersome, they have been obtained through a direct lipase-catalyzed reaction. Capsiate, the ester CAPanalog, was synthesized using a novel enzymatic transacylation one-pot strategy.