title: Two additional bacteriophage-associated glycan hydrolases cleaving ketosidic bonds of 3-deoxy-D-manno-octulosonic acid in capsular polysaccharides of Escherichia coli.
abstract: Two bacteriophages degrading 3-deoxy-D-manno-2-octulosonic acid-(KDO)-containing capsules of Escherichia coli strains were identified. Using modifications of the thiobarbituric acid assay, it was shown that each phage contains a glycan hydrolase activity cleaving one type of ketosidic linkage of KDO. Thus, the enzyme from phage phi 95 catalyzes the hydrolysis of beta-octulofuranosidonic linkages of the K95 glycan; and phi 1092, the alpha-octulopyranosidonic linkages of the K? antigen of E. coli LP1092. No cross-reactivity of the phage enzymes with other KDO-containing capsular polysaccharides was observed.
authors.forename: F
authors.initials: F
authors.lastname: Altmann
authors.forename: L
authors.initials: L
authors.lastname: März
authors.forename: S
authors.initials: S
authors.lastname: Stirm
authors.forename: F M
authors.initials: FM
authors.lastname: Unger
mesh_terms: D000942:Antigens, Bacterial / Q000378:metabolism; D000954:Antigens, Surface / Q000378:metabolism; D001435:Bacteriophages / Q000201:enzymology* / Q000648:ultrastructure; D004926:Escherichia coli / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D008854:Microscopy, Electron; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D013379:Substrate Specificity; D013400:Sugar Acids / Q000378:metabolism*
chemical_list: D000942:Antigens, Bacterial; D000954:Antigens, Surface; C030659:K antigens; D011135:Polysaccharides, Bacterial; D013400:Sugar Acids; C002532:2-keto-3-deoxyoctonate; D006026:Glycoside Hydrolases; C053605:KDO alpha-octulopyranoside hydrolase; C053606:KDO beta-octulofuranoside hydrolase