Satoaki Shibata

Immunochemical Specificities of Antibody to the Heptasaccharide Unit of Plant Xyloglucan

This paper reports the preparation of the antibody specific for the heptasaccharide repeating unit of xyloglucan and characterization of its immunological specificities. The heptasaccharide, octasaccharide and nonasaccharide of xyloglucan were prepared by cellulase hydrolysis of tamarind xyloglucan, followed by gel filtration

Anti-α-L-arabinofuranose antibodies: purification, immunochemical characterization, and use in histochemical studies of plant cell-wall polysaccharides

Abstract Anti-α- l -arabinofuranose antibodies, raised in rabbits by immunization with p-diazophenyl α- l -arabinofuranoside-bovine serum albumin, were purified by affinity chromatography using an α- l -arabinofuranose-Sepharose column. The antibodies, proved by immunoelectrophoresis to be immunoglobulin G (IgG), specifically reacted with α- l -arabinofuranose residues, as confirmed by agar diffusion analysis and inhibition tests. Complement fixation studies showed that the purified antibodies recognize terminal α- l -arabinofuranose residues in glycoconjugates, plant polysaccharides, and synthetic polysaccharides having branches of α- l -arabinofuranosyl groups. The antibodies were shown to provide a useful histochemical probe for detection of arabinose-containing polymers in plant tissues, by either the fluorescence- or the peroxidase-labeled immunostaining method.

Preparation and characterization of antibodies against 6-O-α-D-xylopyranosyl-β-D-glucopyranose (β-isoprimeverose), the disaccharide unit of xyloglucan in plant cell-walls

Abstract The p -aminophenyl β-glycoside of 6- O -α- d -xylopyranosyl- d -glucopyranose (isoprimeverose), the disaccharide unit of plant xyloglucan, was coupled to bovine serum albumin, and the resulting glycoconjugate was used as an immunogen for the immunization of a rabbit. The immunochemical specificities of the rabbit antiserum raised against the glycoconjugate were characterized by immunodiffusion, quantitative precipitation, and hapten inhibition. After removal of anti-bovine serum albumin antibodies, the antiserum exhibited a specificity for the introduced disaccharide unit of the artificial antigen. The antibody-combining site was also shown to recognize the aglycon portion of the introduced hapten. The antiserum interacted with some xyloglucans, such as those from tamarind seed and the cell wall of pea stem. β-Isoprimeverose and α- d -xylopyranosides were good inhibitors of the xyloglucan-antibody precipitation system, indicating that the antibodies recognize the β-isoprimeverose unit of the xyloglucan.

Purification and Some Properties of a-L-Fucosidase Isolated from Streptococcus sanguis

α-L-Fucosidase acting on naturally occurring substrates was highly purified from the growth culture of Streptococcus sanguis ATCC 10557. The molecular weight of the enzyme was approximately 120,000 and the optimal pH was at 5.5. The purified enzyme showed specificity toward the linkage of α-(1→2) fucosides in oligosaccharides and glycoproteins. The enzyme released L-fucose from glycoprotein in human parotid saliva.

Hydrolysis of milk oligosaccharides by the oral bacterium Streptococcus sanguis atcc 10557.

Abstract The sequential degradation of oligosaccharide chains by Strep, sanguis ATCC 10557 was studied using milk oligosaccharides (lacto-N-fucopentaitols) labelled by reduction with tritiated borohydride as substrates. The culture supernatant hydrolysed lacto-N-efucopentaitol I, II or III, and yielded radioactive tetrasaccharides, disaccharides and monosaccharides. Galactonolactone inhibited the hydrolysis of galactosyl β1–3 or -4 N-acetylglucosamine linkage in lacto-N-fucopentaitol II or III, and the tetrasaccharide increased consequently. It is deduced that the exo-type of glycosidases secreated by Strep, sanguis ATCC 10557 sequentially degrade the glycosidic linkages from non-reducing sites of milk oligosaccharides and that the carbohydrate units of saliva glycoproteins may be hydrolysed by oral bacteria.

Changes of Serological Activity by α-L-Fucosidase Isolated from Streptococcus sanguis ATCC 10557

a-L-Fucosidase isolated from the growth culture of Streptococcus sanguis ATCC 10557 acted on H- and Leb-blood group substances in porcine gastric lining, human gastric lining, human ovarian cyst fluid and human whole saliva, with consequent loss of H- and Leb -activities and a concomitant increase of Lea activity.

The Presence of Fucosyltransferases with Different Substrate Specificity in Human Parotid Saliva

Using glycoproteins and milk oligosaccharides as substrate acceptors, we demonstrated at leaet two fucosyltransferases in human parotid saliva. One enzyme transferred L-fucose from GDP-fucose to the C-3 position of N-acetylglucosamine or glucose residue of oligosaccharide chains, and the other transferred to the C-4 position of N-acetylglucosamine residue of oligosaccharide chains.

Separation of Fucosyltransferase and Endogenous Acceptors of Fucose from Human Parotid Saliva

Using gel filtration on Sephadex G-100 and column chromatography on CM-cellulose, fractions containing either endogenous acceptor of L-fucose or fucosyltransferase were obtained from human parotid saliva. Hydrolysis with mild acid followed by Smith degradation increased the fucosyltransferase activity of the fractions that contained endogeneous acceptor.

Extracellular Glycosidases of Some Oral Streptococci

Bacterial glycosidases that cleave carbohydrate components from salivary glycoproteins may be important in oral pathological conditions. The purpose of this study was to survey for the presence of extracellular glycosidases of some oral streptococci.Twenty-four strains of oral streptococci were grown in trypticase soy broth culture at 37°C for 24 hours.The extracellular enzymes in the supernatant of culture were precipitated by the addition of 80% saturation of ammonium sulfate and then dissolved in phosphate buffer (pH 7.0). For the assay of α-L-fucosidase, porcine submaxillary glycoprotein (PSG) and/or p-nitrophenyl-α-L-fucoside (p-NPF) were used as substrates. Neuraminidase activity was determined using human plasma glycoprotein Fr. VI. Using corresponding p-nitrophenylglycosides, other glycosidase (β-galactosidase, β-N-acetylglucosaminidase, α-mannosidase) assays were performed. The free sugar and p-nitrophenol released, each was determined by the spectrophotometric method, respectively.Both activities of α-L-fucosidase against PSG and neuraminidase were found only in S sanguis ATCC 10557 and S. mitis ATCC 9811. α-L-Fucosidase activity against p-NPF was not detectable in any strains. Several strains of S. sanguis possessed both β-galactosidase and β-N-acetylglucosaminidase activities. Only one strain in S. mutans tested produced β-N-acetylglucosaminidase.This study has demonstrated that bacterial glycosidases are produced by some oral streptococci. It is tempting to speculate that the streptococcal glycosidases may play a role in the degradation of salivary glycoproteins.