title: Characterization of alginate lyase from Pseudomonas syringae pv. syringae.
abstract: The gene encoding alginate lyase (algL) in Pseudomonas syringae pv. syringae was cloned, sequenced, and overexpressed in Escherichia coli. Alginate lyase activity was optimal when the pH was 7.0 and when assays were conducted at 42 degrees C in the presence of 0.2 M NaCl. In substrate specificity studies, AlgL from P. syringae showed a preference for deacetylated polymannuronic acid. Sequence alignment with other alginate lyases revealed conserved regions within AlgL likely to be important for the structure and/or function of the enzyme. Site-directed mutagenesis of histidine and tryptophan residues at positions 204 and 207, respectively, indicated that these amino acids are critical for lyase activity.
authors.affiliation: Division of Biomedical Sciences, University of California, Riverside, California 92521, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Preston
authors.forename: T Y
authors.initials: TY
authors.lastname: Wong
authors.forename: C L
authors.initials: CL
authors.lastname: Bender
authors.forename: N L
authors.initials: NL
authors.lastname: Schiller
mesh_terms: D003001:Cloning, Molecular; D005798:Genes, Bacterial; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D011133:Polysaccharide-Lyases / Q000235:genetics / Q000378:metabolism*; D011549:Pseudomonas / Q000201:enzymology* / Q000235:genetics; D012965:Sodium Chloride; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D012965:Sodium Chloride; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase