Chemically modified celluloses. XIII. Periodate oxidation of cellulose dyed with reactive and direct dyes in the presence of electrolytes

1979 ◽  
Vol 24 (11) ◽  
pp. 2269-2276
Author(s):  
V. A. Shenai ◽  
K. P. Pai
2010 ◽  
Vol 88 (3) ◽  
pp. 513-525 ◽  
Author(s):  
Marie-Rose Van Calsteren ◽  
Fleur Gagnon ◽  
Sonia Lacouture ◽  
Nahuel Fittipaldi ◽  
Marcello Gottschalk

The capsular polysaccharide (CPS) of Streptococcus suis serotype 2 was isolated, purified, chemically modified, and characterized. Sugar and absolute configuration analyses of the CPS gave the following composition: d-Gal, 3; d-Glc, 1; d-GlcNAc, 1; d-Neu5Ac, 1; l-Rha, 1. Sialic acid was found to be terminal, and the CPS was quantitatively desialylated by mild acid hydrolysis. The CPS was also submitted to periodate oxidation followed by borohydride reduction and Smith degradation. Sugar and methylation analysis,1H and13C nuclear magnetic resonance, and mass spectrometry of the native CPS or of its specifically modified products allowed to determine the repeating unit sequence: [4)[Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)]Gal(β1–4)[Gal(α1–3)]Rha(β1–4)Glc(β1-]n. The backbone sequence was found to be identical to that of Streptococcus agalactiae or group B Streptococcus (GBS) type VIII and Streptococcus pneumoniae type 23F. The S. suis CPS shares the sequence Neu5Ac-Gal-GlcNAc-Gal in common with GBS types Ia, Ib, II, III, and IV CPSs but differs from them by the presence of rhamnose and the fact that sialic acid is 2,6- rather than 2,3-linked to the following Gal. A correlation between the S. suis CPS sequence and genes of the serotype 2 cps locus encoding putative enzymes responsible for the biosynthesis of the repeating unit was tentatively established.


2013 ◽  
Vol 91 (2) ◽  
pp. 49-58 ◽  
Author(s):  
Marie-Rose Van Calsteren ◽  
Fleur Gagnon ◽  
Cynthia Calzas ◽  
Guillaume Goyette-Desjardins ◽  
Masatoshi Okura ◽  
...  

The capsular polysaccharide (CPS) of Streptococcus suis serotype 14 was purified, chemically modified, and characterized. Sugar and absolute configuration analyses gave the following CPS composition: d-Gal, 3; d-Glc, 1; d-GlcNAc, 1; d-Neu5Ac, 1. The Sambucus nigra lectin, which recognizes the Neu5Ac(α2–6)Gal/GalNAc sequence, showed binding to the native CPS. Sialic acid was found to be terminal, and the CPS was quantitatively desialylated by mild acid hydrolysis. It was also submitted to periodate oxidation followed by borohydride reduction and Smith degradation. Sugar and methylation analyses,1H and13C nuclear magnetic resonance, and mass spectrometry of the native CPS or of its specifically modified products allowed to determine the repeating unit sequence: [6)[Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)]Gal(β1–3)Gal(β1–4)Glc(β1–]n. S. suis serotype 14 CPS has an identical sialic acid-containing side chain as serotype 2 CPS, but differs by the absence of rhamnose in its composition. The same side chain is also present in group B Streptococcus type Ia CPS, except that in the latter sialic acid is 2,3- rather than 2,6-linked to the following galactose. A correlation between the S. suis CPS sequence and genes of the serotype 14 cps locus encoding putative glycosyltransferases and polymerase responsible for the biosynthesis of the repeating unit is proposed.


Author(s):  
Masaatsu Koike ◽  
Koichi Nakashima ◽  
Kyoko Iida

Penicillin exerts the activity to inhibit the peptide cross linkage between each polysaccharide backbone at the final stage of wall-peptidoglycan biosynthesis of bacteria. Morphologically, alterations of the septal wall and mesosome in gram-positive bacteria, which were occurred in early time after treatment with penicillin, have been observed. In this experiment, these alterations were cytochemically investigated by means of silver-methenamine staining after periodate oxidation, which is applied for detection of localization of wall mucopolysaccharide.Staphylococcus aureus strain 209P treated with 100 u/ml of penicillin G was divided into two aliquotes. One was fixed by Kellenberger-Ryter's OSO4 fixative at 30, 60 and 120 min after addition of the antibiotic, dehydrated through alcohol series, and embedded in Epon 812 (Specimen A). The other was fixed by 21 glutaraldehyde, dehydrated through glycolmethacrylate series and embedded in glycolmethacrylate mixture, according to Bernhard's method (Specimen B).


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