title: Occurrence of 2,4-dihydroxy-3,3,4-trimethylpyroglutamic acid as an N-acyl substituent in the O-polysaccharide chain of the lipopolysaccharide of Vibrio anguillarum V-123.
abstract: A new and highly branched amino acid was found as an N-acyl substituent of the O-polysaccharide chain obtained from the lipopolysaccharide of Vibrio anguillarum V-123 (serogroup JO-2) and evidence is presented to support the structure as 2,4-dihydroxy-3,3,4-trimethylpyroglutamic acid. Acid hydrolysis of the O-polysaccharide gave the lactone of 2,4-dihydroxy-3,3,4-trimethylglutamic acid, together with 2-amino-2-deoxy-D-galacturonic acid, 2-amino-2,6-dideoxy-D-glucose (D-quinovosamine), and 4-amino-4,6-dideoxy-D-glucose (D-viosamine). Degradation of the O-polysaccharide with hydrogen fluoride yielded a fragment (H1) that was indicated by the 1H-NMR data to be 4-amino-4,6-dideoxy-D-glucose N-acetylated with 2,4-dihydroxy-3,3,4-trimethylpyroglutamic acid. The configuration of the amino acid was not determined.
authors.affiliation: Department of Chemistry, Faculty of Science, Hokkaido University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Eguchi
authors.forename: S
authors.initials: S
authors.lastname: Kaya
authors.forename: Y
authors.initials: Y
authors.lastname: Araki
mesh_terms: D000596:Amino Acids / Q000032:analysis; D002236:Carbohydrate Conformation; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D007202:Indicators and Reagents; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D014733:Vibrio / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D007202:Indicators and Reagents; D008070:Lipopolysaccharides; D011135:Polysaccharides, Bacterial; C077093:2,4-dihydroxy-3,3,4-trimethylpyroglutamic acid; D011761:Pyrrolidonecarboxylic Acid