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In recent years, the synthesis of human milk oligosaccharides, particularly fucooligosaccharides, has been investigated. These oligosaccharides provide protection against gastrointestinal diseases for newborns, among other functionalities. α-L-fucosidase from Thermotoga maritima of GH29 family has been reported to produce fucooligosaccharides by means of a transfucosylation reaction. However, the interaction between acceptor and donor substrates, and the enzyme has been little studied. For that reason, and due to the importance of fucooligosaccharides, the present study proposes a theoretical synthesis route employing α-L-fucosidase from T. maritima, lactose as acceptor substrate and pNP-fucose as fucosyl donor. A molecular docking study was carried out using crystallographic structure of α-L-fucosidase from Protein Data Bank. By simulating the theoretical synthesis with T. maritima fucosidase, it was observed that lactose interacts with the enzyme in regions other than the active site. However, it is approaching the active site when the fucose is in the position to form the enzyme-substrate complex. This finding may explain the transfucosylation yield documented in the literature when the proportion of fucosyl acceptor substrate increases concerning that of the donor substrate. [ABSTRACT FROM AUTHOR]

The effects of water activity (aw), pH, and temperature on transglycosylation activity of α-L-fucosidase from Thermotoga maritima in the synthesis of fucosylated oligosaccharides were evaluated using different water-organic cosolvent reaction systems. The optimum conditions of transglycosylation reaction were the pH range between 7 and 10 and temperature 90–95 °C. The addition of organic cosolvent decreased α-L-fucosidase transglycosylation activity in the following order: acetone > dimethyl sulfoxide (DMSO) > acetonitrile (0.51 > 0.42 > 0.18 mM/h). However, the presence of DMSO and acetone enhanced enzyme-catalyzed transglycosylation over hydrolysis as demonstrated by the obtained transglycosylation/hydrolysis rate (rT/H) values of 1.21 and 1.43, respectively. The lowest rT/H was calculated for acetonitrile (0.59), though all cosolvents tested improved the transglycosylation rate in comparison to a control assay (0.39). Overall, the study allowed the production of fucosylated oligosaccharides in water-organic cosolvent reaction media using α-L-fucosidase from T. maritima as biocatalyst. [ABSTRACT FROM AUTHOR]

Cellulosimicrobium strain SE3T was isolated from the San Elijo coastal lagoon near San Diego. A whole genome-based phylogenetic comparison shows great heterogeneity within the Cellulosimicrobium genus. Based on average nucleotide identity, whole genome-based comparison, and the presence of a unique l-fucose metabolic pathway, strain SE3T was shown to belong to a novel species within the genus, together with five other strains. The name Cellulosimicrobium fucosivorans sp. nov. is proposed, with strain SE3T as the type strain. The strain encodes a unique alpha-l-fucosidase and the l-fucose metabolic pathway is homologous to the one recently described in Campylobacter jejuni. C. fucosivorans is able to grow on l-fucose, and interestingly, the biosynthesis of the yellow carotenoid is dependent on the presence of l-fucose in the media. The ability to metabolize fucose and the linked production of carotenoids are expected to provide C. fucosivorans with a competitive advantage in the sunny coastal lagoon area. [ABSTRACT FROM AUTHOR]

Fucosylated oligosaccharides present in human milk perform various biological functions that benefit infants' health. These compounds can be also obtained by enzymatic synthesis. In this work, the effect of the immobilization of α-l-fucosidase from Thermotoga maritima on the synthesis of fucosylated oligosaccharides was studied, using lactose and 4-nitrophenyl-α-l-fucopyranoside (pNP-Fuc) as acceptor and donor substrates, respectively, and Eupergit® CM as an immobilization support. The enzyme was immobilized with 90% efficiency at pH 8 and ionic strength of 1.5 M. Immobilization decreased enzyme affinity for the donor substrate as shown by a 1.5-times higher KM value and a 22-times decrease of the kcat/KM ratio in comparison to the unbound enzyme. In contrast, no effect was observed on the synthesis/hydrolysis ratio (rs/rh) when α-l-fucosidase was immobilized. Also, the effect of initial concentration of substrates was studied. An increase of the acceptor concentration improved the yields of fucosylated oligosaccharides regardless enzyme immobilization. The synthesis yields of 38.9 and 40.6% were obtained using Eupergit® CM-bound or unbound enzyme, respectively, and 3.5 mM pNP-Fuc and 146 mM lactose. In conclusion, α-l-fucosidase from Thermotoga maritima was efficiently immobilized on Eupergit® CM support without affecting the synthesis of fucosylated oligosaccharides. [ABSTRACT FROM AUTHOR]

The influence of CaCl2 and NaCl in the hydrolytic activity and the influence of CaCl2 in the synthesis of fucosylated oligosaccharides using α-L-fucosidase from Thermotoga maritima were evaluated. The hydrolytic activity of α-L-fucosidase from Thermotoga maritima displayed a maximum increase of 67% in the presence of 0.8 M NaCl with water activity (aw) of 0.9672 and of 138% in the presence of 1.1 M CaCl2 (aw 0.9581). In addition, the hydrolytic activity was higher when using CaCl2 compared to NaCl at aw of 0.8956, 0.9581 and 0.9672. On the other hand, the effect of CaCl2 in the synthesis of fucosylated oligosaccharides using 4-nitrophenyl-fucose as donor substrate and lactose as acceptor was studied. In these reactions, the presence of 1.1 M CaCl2 favored the rate of transfucosylation, and improved the yield of synthesis duplicating and triplicating it with lactose concentrations of 58 and 146 mM, respectively. CaCl2 did not significatively affect hydrolysis rate in these reactions. The combination of the activating effect of CaCl2, the decrement in aw and lactose concentration had a synergistic effect favoring the synthesis of fucosylated oligosaccharides. [ABSTRACT FROM AUTHOR]

Fucosylated oligosaccharides, such as 2′-fucosyllactose in human milk, have important biological functions such as prebiotics and preventing infection. In this work, the effect of an acceptor substrate (lactose) and the donor substrate 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) on the synthesis of a fucosylated trisaccharide was studied in a transglycosylation reaction using α-L-fucosidase from Thermotoga maritima. Conducting a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), it was demonstrated that synthesized oligosaccharide corresponded to a fucosylated trisaccharide, and high-performance liquid chromatography (HPLC) of the hydrolyzed compound confirmed it was fucosyllactose. As the concentration of the acceptor substrate increased, the concentration and synthesis rate of the fucosylated trisaccharide also increased, and the highest concentration obtained was 0.883 mM (25.2% yield) when using the higher initial lactose concentration (584 mM). Furthermore, the lower donor/acceptor ratio had the highest synthesis, so at the molar ratio of 0.001, a concentration of 0.286 mM was obtained (32.5% yield). [ABSTRACT FROM AUTHOR]

The ability to produce extracellular enzymes of carbon metabolism was studied in 55 strains related to 18 taxa and isolated from various habitats. Production of a number of enzymes was found to depend on the source from which the strains were isolated. Among the strains associated with algae and marine invertebrates, the highest number of producers were found in the seawater of Primorski krai. The strains isolated from this temperate climatic zone possessed higher enzymatic activity than those isolated from the tropical zone. The results obtained in the current research are useful for further directed searching for the producers of specific O-glycoside hydrolases. [ABSTRACT FROM AUTHOR]

We assayed plasma activities of Β-galactosidase, Β-hexosaminidase, α-mannosidase, α-fucosidase and α-galactosidase involved in degradation of the glycoprotein molecule in 110 insulin-dependent diabetics aged 3-1/2 to 19 years and compared them to a group of normal youngsters. We correlated the plasma enzyme activities with the duration, control and sequelae of insulin-dependent diabetes. Insulin-dependent diabetics had a significantly higher plasma activity of Β-hexosaminidase and α-mannosidase (p<0.01) and a significantly lower plasma activity of α-fucosidase and α-galactosidase (p<0.01). Of the 5 enzymes studied, only plasma Β-hexosaminidase correlated with fasting and postprandial blood sugar (p<0.01), cholesterol and triglycerides (p<0.05). Additionally, poor control of diabetes was also associated with a significantly higher plasma Β-hexosaminidase activity (p<0.01). Proteinuria or an abnormal Addis count suggestive of renal involvement was associated with various changes in plasma acidic hydrolases. These changes may be related to insulin deficiency rather than hyperglycemia and may be genetically determined. [ABSTRACT FROM AUTHOR]

The activity of fucosidase shows different value depending on disease, eg) fucosidosis and I cell disease are characterized by the absence or deficiences of α-fucosidase, and sera of ovarian cancer patients exhibited a statistically significant deficiency of α-L-fucosidase activity (Zielke et al., 1972; Kress et al., 1980; Barlow et al., 1981). For the purpose of diagnosis of these disease easily, the manual of test can be developed by preparing kits of hydrophobic-binding substrate of fucosidase that bind C18-column. [ABSTRACT FROM AUTHOR]