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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The capsular polysaccharide from Haemophilus influenzae type b (polyribosyl ribitol-phosphate; PRP) and the capsular polysaccharides from Streptococcus pneumoniae types 6B, 14, 18C, and 23F (Pn6B, Pn14, Pn18C, and Pn23F) were subjected to acid hydrolysis using hydrofluoric (HF) and/or trifluoroacetic acid (TFA) and high-pH anion-exchange chromatography with pulsed amperometric detection in an effort to identify optimum hydrolysis conditions for composition analysis of their carbohydrate components. With the exception of PRP, composition analyses of polysaccharides containing a phosphate moiety in the repeating unit structure (Pn6B, Pn18C, and Pn23F) are significantly improved by subjecting the sample to HF hydrolysis (65 degrees C, 1 h) followed by TFA hydrolysis (98 degrees C, 16 h). This results in essentially quantitative hydrolysis of the phosphodiester bond to the carbohydrate components, which otherwise remained predominantly phosphorylated and poorly accounted for in the analysis. Optimum analysis of PRP was achieved following a 2-h hydrolysis with TFA at 80 degrees C, whereas Pn14 showed optimum results after a 16-h hydrolysis with TFA at 98 degrees C. These analyses also provide information about the relative susceptibility to acid hydrolysis of the various glycosidic and phosphodiester bonds in these polysaccharides, with evidence to suggest that the acid lability of a given bond can be dramatically different from one polysaccharide to another.
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PMID:Carbohydrate composition analysis of bacterial polysaccharides: optimized acid hydrolysis conditions for HPAEC-PAD analysis. 163 23

The taxonomic distinction between Actinobacillus (Haemophilus) actinomycetemcomitans and Haemophilus aphrophilus and the taxonomic distinction between H. aphrophilus and Haemophilus paraphrophilus have been questioned. This study was done to determine whether multivariate statistical analyses of carbohydrate data from lipopolysaccharides could be used to distinguish between these closely related species. Lipopolysaccharides were extracted with phenol-water and purified. Carbohydrates were assessed by using gas chromatography and gas chromatography-mass spectrometry after methanolysis and derivatization with trifluoroacetic acid anhydride. The lipopolysaccharides from all of the species contained rhamnose, fucose, galactose, glucose, L-glycero-D-mannoheptose, and glucosamine plus galactosamine, but in varying amounts. A. actinomycetemcomitans and H. paraphrophilus also contained D-glycero-D-mannoheptose, while H. aphrophilus did not. Sample- and variable-oriented principal-component analyses of the carbohydrate data clearly distinguished among A. actinomycetemcomitans, H. aphrophilus, and H. paraphrophilus. Soft independent modelling of class analogy showed that no sample in the A. actinomycetemcomitans class fell within the 95% confidence limits of the H. aphrophilus class. H. paraphrophilus fell outside both classes.
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PMID:Multivariate analyses of carbohydrate data from lipopolysaccharides of Actinobacillus (Haemophilus) actinomycetemcomitans, Haemophilus aphrophilus, and Haemophilus paraphrophilus. 227 55

A method based on whole-cell methanolysis and trifluoroacetic acid anhydride derivatization was developed for routine laboratory differentiation between isolates from the Actinobacillus--Haemophilus--Pasteurella group. All species, except Haemophilus aphrophilus, contained D-glycero-D-mannoheptose, although in varying concentrations. The distribution of this sugar could be used to distinguish H. aphrophilus from Actinobacillus actinomycetemcomitans, H. paraphrophilus, H. influenzae type b, Pasteurella haemolytica, P. multocida and P. ureae, and also H. influenzae type b from Pasteurellae. The pattern of major sugars in P. ureae and P. haemolytica resembled that of A. actinomycetemcomitans. Major fatty acids of the whole-cell methanolysates provided no basis of interspecies differentiation.
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PMID:Differentiation between major species of the Actinobacillus--Haemophilus--Pasteurella group by gas chromatography of trifluoroacetic acid anhydride derivatives from whole-cell methanolysates. 404 43

In the present study, the closely related facultative, Gram-negative rods, Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus, were distinguished taxonomically by means of their carbohydrate composition in phenol-extracted lipopolysaccharide. Both A. actinomycetemcomitans and H. aphrophilus lipopolysaccharide contained rhamnose, fucose, galactose, glucose, L-glycero-D-mannoheptose, galactosamine, and glucosamine. The content of galactose was approximately twice as high in lipopolysaccharide from H. aphrophilus as in lipopolysaccharide from A. actinomycetemcomitans. D-Glycero-D-mannoheptose was detected exclusively in lipopolysaccharide from A. actinomycetemcomitans where it constituted 11.8-16.7% of the sugar content. This aldoheptose may therefore serve as a marker for chemotaxonomic differentiation between A. actinomycetemcomitans and H. aphrophilus. The present study also describes fragmentation of methylheptoside derivatives of trifluoroacetic acid (D-glycero- and L-glycero-D-mannoheptose) from A. actinomycetemcomitans as suggested by mass spectrometry.
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PMID:Differentiation between Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus based on carbohydrates in lipopolysaccharide. 651 46