Просмотр исходного текста страницы Mlg-Glycosyl-Hydrolase-Lichenase-Tool-Characterization-Mlgs-q

It holds potential for application in the brewery, animal feed, and biofuel industries. Several defined MLG oligosaccharides obtained by automated glycan assembly are used to analyze the substrate specificities of Bacillus subtilis lichenase. Two glucose building blocks (BBs), equipped with a temporary fluorenylmethyloxycarbonyl chloride (Fmoc) protecting group in the C-3 or C-4 position, served to assemble different oligosaccharides by using an automated oligosaccharide synthesizer. Light-induced cleavage of the glycan products from the solid support followed by global deprotection provided seven MLG oligosaccharides of different length and connectivity. After incubation of the MLG oligosaccharides with lichenase, the digestion products were analyzed by HPLC-MS. These digestion experiments provided insights into the enzyme's active site that is in line with other recent evidence suggesting that the substrate specificity of lichenases has to be reconsidered.<br /><br /> These results demonstrate that synthetic MLG oligosaccharides are useful tools to analyze mixed-linkage Alpha-3-fucosyltransferases and their glycoconjugate antigen products in the Candelier JJ(1), Mollicone R, Mennesson B, Bergemer AM, Henry S, Coullin P, BACKGROUND Three patterns of alpha-3-fucosyltransferase activity have been described in human adult tissues with different acceptor specificity myeloid, plasma and Lewis. Five- to ten-week embryos express the myeloid enzyme in all tissues tested, then this enzyme is replaced by plasma or Lewis enzymes, with the exception of leukocytes that continue to express the myeloid form of the enzyme in the adult. These enzymes have not been studied as yet in the EXPERIMENTAL DESIGN The three different alpha-3-fucosyltransferases were studied in homogenates of mesonephros and metanephros with synthetic oligosaccharide acceptors. The oligosaccharide precursors and products of these enzymes (precursor, H, Le(a), sialyl-Le(a) and Le(b) for type 1 and precursor, H, Le(x), sialyl-Le(x) and Le(y) for type 2) were localized by immunofluorescence with specific antibodies.RESULTS Only the myeloid alpha-3-fucosyltransferase is detected at 5 weeks in mesonephros and it disappears at 8 weeks. In metanephros, the myeloid enzyme alone is detected between weeks 6 and 8. The plasma enzyme then appears and only at the last trimester of gestation does the Lewis enzyme appear.<br /><br /> Three histologic patterns that are concordant with the expression of the alpha-3-fucosyltransferases are observed I. Inducer, S-shaped body, Bellini and calyce express Le(x) at an early stage when, only the myeloid alpha-3-fucosyltransferase is detected; II. Later, [https://en.wikipedia.org/wiki/Lacto-N-tetraose Snag it now] and descending limbs of Henle's loop express Le(x) (week 9) and sialyl-Le(x) (week 16) when the plasma alpha-3-fucosyltransferase appears; III. Calyceal and collecting systems always express Le(x) and after week 12 Le(a) and Le(b) appear, in accordance with the late appearance of Lewis CONCLUSIONS The sequential appearance of enzymes and their products suggests that during renal organogenesis the myeloid alpha-3-fucosyltransferase is progressively replaced by the plasma enzyme in the proximal tubules and later by the Lewis enzyme in Bellini's ducts and calyce.Preparation, structural characterization and prebiotic potential of mulberry Hu TG(1), Wu H(2), Yu YS(1), Xu YJ(1), Li EN(1), Liao ST(1), Wen P(3), Zou Agricultural SciencesKey Laboratory of Functional Foods, Ministry of Agriculture and Rural AffairsGuangdong Key Laboratory of Agricultural Products TechnologyGuangdong Province Key Laboratory for Green Processing of Natural The present study shows the purification of a main oligosaccharide fraction (MLO 1-2) from the enzymatic hydrolysate of mulberry leaf polysaccharides by DEAE-52 cellulose and gel column chromatography. The physicochemical properties of MLO 1-2 were characterized. The structure of MLO 1-2 was obtained as follows α-(2-OAc)-Manp-1 → 2-β-Glcp-1 → 4-β-Glcp-1 → 4-α-Glcp-1 → 2-α-Glcp-1 → 2-α-Galp-1 → 2-β-Galp-1 → 2-β-Galp-1, which was elucidated by methylation and NMR analysis.<br /><br /> The molecular weight of MLO 1-2 showed no significant change after simulated saliva, gastric and intestinal digestion. [http://www.allinno.com/product/healthcare/674.html Seebio lacto n neotetraose] indicated that MLO 1-2 could pass through the digestive system without being degraded to safely reach the colon to regulate the gut microbiota. Additionally, MLO 1-2, more than glucose or galactooligosaccharides, promoted the proliferation of Bifidobacterium bifidum, B. adolescentis, Lacticaseibacillus rhamnosus and Lactobacillus acidophilus. Furthermore, the acetic and lactic acid concentrations of bacterial cultures inoculated with MLO 1-2 were higher than those inoculated with glucose and galactooligosaccharide (GOS).