Modifications of the Park-Johnson ferricyanide submicromethod for the assay of reducing groups in carbohydrates

To analyze the fine specificity of the protective IgG response for the capsule of group B Neisseria meningitidis (Men B) induced after immunization with live bacteria, two specific IgG2a monoclonal antibodies (mAb) have been generated from hyperimmunized Balb/c and NZB mice (101C11 and 30H12). They specifically recognize in direct and competitive binding assays the capsular polysaccharides of Men B and Escherichia coli k1 on condition that the length of the polysaccharidic chain is sufficient to make a conformational structure (more than 15 monomers of alpha (2-->8) linked N-acetyl neuraminic acid). They do not interact with group A and group C Neisseria meningitidis polysaccharides in ELISA. A chemical derivative of the Men B polysaccharide, the N-propionylated Men B polysaccharide, considered as mimicking a unique bactericidal epitope on the surface of Men B is recognized by 101C11 but not by 30H12. The two mAb have, in vitro, a specific bactericidal activity against live Men B which do not seem serotype specific. Moreover, the killing of Men B mediated by 30H12 can be neutralized by an anti-idiotypic mAb (216F11) generated from A/J mice, immunized with polymerized 30H12. These data show that at least two distinct bactericidal epitopes exist on the surface of the Men B capsule.

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“…The reducing sugar concentration was measured by a modification of the Park-Johnson ferricyanide submicromethod (16,17).…”

Section: Methodsmentioning

confidence: 99%

Bactericidal Activity of Two IgG_2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide

Hurpin¹,

Carosella²,

Cazenave³

1992

Hybridoma

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“…Carbohydrate concentration in each fraction was measured by phenol-sulfuric acid method (Rao and Pattabiraman 1989). Reducing end groups were determined by potassium ferricyanide method (Porroo et al 1981). The average chain length (CL) was calculated from the amounts of carbohydrate and the number of reducing ends (Asaoka et al 1985).…”

Section: Analysis Of Starch Structurementioning

confidence: 99%

Temperature induced changes in the starch components and biosynthetic enzymes of two rice varieties

et al. 2005

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The effects of temperature on starch and amylose accumulation, fine structure of amylopectin and activities of some enzymes related to starch synthesis in developing rice endosperms was examined. Two early indica rice varieties were used, differing in amylose concentration (AC, %), namely Jia 935 (low AC) and Jia 353 (high AC). The results showed that the effects of high temperature on AC and amylopectin fine structure were variety-dependent. High temperature caused a reduction in amylose concentration and an increase in the short chain (CL<22) proportion of amylopectin for Jia 935; while opposite was true for Jia 353. High temperature also reduced and increased the activity of granulebound starch synthase (GBSS) in Jia 935 and in Jia 353, respectively. This suggests that a change in the ratio of amylose/starch due to temperature was attributable to a change in GBSS activity. Moreover, obvious differences between the two rice varieties were detected in the activities of sucrose synthase (SuSy), ADP-glucose pyrophosphorylase (ADPG-Ppase), soluble starch synthase (SSS), starch branching enzyme (SBE), starch de-branching enzyme (SDBE) and starch phosphorylase (SPase) to high temperature. Accumulation rate of amylose was significantly and positively correlated with GBSS for Jia 935, but not for Jia 353. Amylose accumulation was also significantly and positively correlated with the activities of SDBE, SBE, ADPG-Ppase and SuSy for both varieties. The results suggest that the ratio of amylose to starch in rice endosperm is not only related to GBSS, but also affected by the activities of SDBE, SBE, ADPG-Ppase and SuSy.

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“…Following neutralization the monosaccharide content was determined according to Porro et al (15). For calibration a glucose standard was used.…”

Section: Carbohydrate Quantificationmentioning

confidence: 99%

Polysaccharide Fraction from Higher Plants which Strongly Interacts with the Cytosolic Phosphorylase Isozyme

Yang¹,

Steup²

1990

Plant Physiol.

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From leaves of Spinacia oleracea L. or from Pisum sativum L. and from cotyledons of germinating pea seeds a high molecular weight polysaccharide fraction was isolated. The apparent size of the fraction, as determined by gel filtration, was similar to that of dextran blue. Following acid hydrolysis the monomer content of the polysaccharide preparation was studied using high pressure liquid and thin layer chromatography. Glucose, galactose, arabinose, and ribose were the main monosaccharide compounds. The native polysaccharide preparation interacted strongly with the cytosolic isozyme of phosphorylase (EC 2.4.1.1).Interaction with the plastidic phosphorylase isozyme(s) was by far weaker. Interaction with the cytosolic isozyme was demonstrated by affinity electrophoresis, kinetic measurements, and by 14C-labeling experiments in which the glucosyl transfer from[14C]glucose 1-phosphate to the polysaccharide preparation was monitored.In higher plants, several enzymes that act on a-1,4/1,6-linked glucans are not restricted to the plastid compartment but rather occupy dual (or, possibly, multiple) intracellular locations (1,16,20). Among these enzymes are endoamylase (EC 3.2.1.1) (9,11,13,14), exoamylase (EC 3.2.1.2) (25), debranching enzyme (EC 3.2.1.41) (14), D-enzyme (EC 2.4.1.8) (10,11,14), and glucan phosphorylase (EC 2.4.1.1) (13, 14, 2 1). As a further complication, an apoplastic location ofan endomylase form has been reported (2). Thus, it appears that both biochemistry and compartmentation of the plant polyglucan metabolism are unexpectedly complex. Whereas for some of the enzymes mentioned above the extraplastidic compartment in which a major proportion of their activities resides has not been precisely defined, both cell fractionating and immunochemical studies have shown that glucan phosphorylase exists as chloroplast-and cytosol-specific enzyme forms which are located within the same mesophyll cell (4,14,18,21 Compartment-specific phosphorylase isozymes from several plant species have been characterized with respect to their kinetic properties (4,17,19,22). These studies have shown that the chloroplast-and cytosol-specific enzyme forms differ strikingly in their glucan specificities. The chloroplast isozyme possesses a high affinity towards maltodextrins, whereas the affinity of the cytosolic isozyme towards oligoglucans is approximately one order of magnitude lower. In contrast, the cytosolic phosphorylase has an extremely high affinity towards highly branched polyglucans, such as glycogen, which are poor substrates for the plastidic counterpart. Even under noncatalytic conditions (i.e

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Modifications of the Park-Johnson ferricyanide submicromethod for the assay of reducing groups in carbohydrates

Cited by 23 publications

References 1 publication

Bactericidal Activity of Two IgG_2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide

Bactericidal Activity of Two IgG_2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide

Temperature induced changes in the starch components and biosynthetic enzymes of two rice varieties

Polysaccharide Fraction from Higher Plants which Strongly Interacts with the Cytosolic Phosphorylase Isozyme

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Modifications of the Park-Johnson ferricyanide submicromethod for the assay of reducing groups in carbohydrates

Cited by 23 publications

References 1 publication

Bactericidal Activity of Two IgG2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide

Bactericidal Activity of Two IgG2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide

Temperature induced changes in the starch components and biosynthetic enzymes of two rice varieties

Polysaccharide Fraction from Higher Plants which Strongly Interacts with the Cytosolic Phosphorylase Isozyme

Contact Info

Product

Resources

About

Bactericidal Activity of Two IgG_2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide

Bactericidal Activity of Two IgG_2aMurine Monoclonal Antibodies with Distinct Fine Specificities for Group BNeisseria meningitidisCapsular Polysaccharide