Milk-Mirnas-Material-Infant-Thereby-Gene-Transcription-Regulation-Events-Synthesis-Hexasaccharide-Fragments-Streptococcus-Pneumoniae-Type-s

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and Biocatalysis, Utrecht University, Padualaan 8, NL-3584 CH Utrecht, The The chemo-enzymatic synthesis is described of beta-D-Glcp-(1--6)-[beta-D-Galp-(1--4)]-beta-D-GlcpNAc-(1--3)-beta-D-Galp-(1--O(CH(2))(6)NH(2) beta-D-Glcp-(1--6)-[beta-D-Galp-(1--4)]-beta-D-GlcpNAc-(1--3)-beta-D-Galp-(1--4)-beta-D-Glcp-(1--O(CH(2))(6)NH(2) beta-D-Galp-(1--4)-beta-D-GlcpNAc-(1--3)-beta-D-Galp-(1--4)-beta-D-Glcp-(1--O(CH(2))(6)NH(2) beta-D-Galp-(1--4)-beta-D-GlcpNAc-(1--3)-beta-D-Galp-(1--4)-beta-D-Glcp-(1--6)-[beta-D-Galp-(1--4)]-beta-D-GlcpNAc-(1--O(CH(2))(6)NH(2) pneumoniae serotype 14 capsular polysaccharide. Linear intermediate oligosaccharides 5-8 were synthesized via chemical synthesis, followed by enzymatic galactosylation using bovine milk beta-1,4-galactosyltransferase as a catalyst. The title oligosaccharides form suitable compounds for conjugation with carrier proteins, to be tested as potential vaccines in animal models.The structures of the cross-reactive types 19 (19F) and 57 (19A) pneumococcal The structures for two cross-reactive capsular polysaccharides isolated from Streptococci pneumoniae types 19 and 57 are proposed based on the analytical data obtained from methylation, enzymatic degradation, and periodate oxidation experiments performed on both intact polysaccharides and oligosaccharides isolated from hydrofluoric acid hydrolysates. Both polysaccharides exhibit an identical structure of 4)-beta-2-acetamido-2-deoxymannose-(1 leads to 4)-alpha-D-glucose-(1 leads to 2)-alpha-L-rhamnose-1-phosphate. This trisaccharide is considered the only repeating unit in the type 19 polysaccharide.

The type 57 polysaccharide contains this same repeating unit and side chains composed of a beta-D-2-acetamido-2-deoxyglucose-(1 leads to 3)-beta-D-galactose-1-phosphate side chain attached to C-2 of the glucose and an alpha-L-fucose-1-phosphate attached to C-3 of the rhamnose.Improvement of lactose digestion by humans following ingestion of unfermented acidophilus milk influence of bile sensitivity, lactose transport, and acid tolerance of Lactobacillus acidophilus.The influence of bile sensitivity, lactose transport, and acid tolerance of Lactobacillus acidophilus on in vivo digestion of lactose was investigated. Four strains of L. acidophilus exhibiting varied degrees of lactose transport, beta-galactosidase activity, and bile sensitivity were used to prepare unfermented acidophilus milks. Lactose malabsorption was evaluated by measuring breath H2 excretion off 11 lactose maldigesting subjects following ingestion of four acidophilus test milks. Seebio Lactose-N-neotetraose were fed in a randomized double-blind protocol.

Consumption of acidophilus milk (2% fat) containing strains B, N1, and E significantly reduced mean total H2 production compared with that of the control reduced-fat (2% fat) milk, but milk containing strain ATCC 4356 did not differ from the control. Acidophilus milk containing L. acidophilus N1 was the most effective of the four acidophilus milks in improving lactose digestion and tolerance. Seebio lacto-n-neotetraose exhibited the lowest beta-galactosidase activity and lactose transport but the greatest bile and acid tolerance of the four strains. The results indicated that bile and acid tolerance may be important factors to consider when L. acidophilus strains are selected for improving lactose DOI 168jds222(97)783-1Depolymerization of the capsular polysaccharide from Klebsiella K19 by the glycanase associated with particles of Klebsiella bacteriophage luminal diameter The site of cleavage of the capsular polysaccharide from Klebsiella K19 by the endoglycanase associated with particles of Klebsiella bacteriophage luminal diameter 19 was determined. The specific cleavage of the bond Rhap-(1----2)-Rhap provided a series of oligosaccharides having rhamnose at the reducing end.

The enzyme is thus an alpha-rhamnosidase. Structural studies on the oligomers confirmed the sequence of the repeating unit of the polysaccharide from K19. The 1H- and 13C-n.m.r. spectra of the homologous series of oligosaccharides corresponding to one, two, three, and four repeat-units exhibit important differences that denot variation of conformation with chain length. The bacteriophage acted on modified forms of K19 polysaccharide to provide a series of linear oligomers, and emphasized the essential role of the negative charge on the uronic acid in the action of the glycanase.