title: Cloning and characterization of a novel oligoalginate lyase from a newly isolated bacterium Sphingomonas sp. MJ-3.
abstract: A bacterium possessing alginate-degrading activity was isolated from marine brown seaweed soup liquefied by salted and fermented anchovy. The isolated strain was designated as Sphingomonas sp. MJ-3 based on the analyses of 16S ribosomal DNA sequences, 16S-23S internal transcribed spacer region sequences, biochemical characteristics, and cellular fatty acid composition. A novel alginate lyase gene was cloned from genomic DNA library and then expressed in Escherichia coli. When the deduced amino acid sequence was compared with the sequences on the databases, interestingly, the cloned gene product was predicted to consist of AlgL (alginate lyase L)-like and heparinase-like protein domain. The MJ-3 alginate lyase gene shared below 27.0% sequence identity with exolytic alginate lyase of Sphingomonas sp. A1. The optimal pH and temperature for the recombinant MJ-3 alginate lyase were 6.5 and 50°C, respectively. The final degradation products of alginate oligosaccharides were analyzed by electrospray ionization mass spectrometry and proved to be alginate monosaccharides. Based on the results, the recombinant alginate lyase from Sphingomonas sp. MJ-3 is regarded as an oligoalginate lyase that can degrade oligoalginate and alginate into alginate monosaccharides.
authors.affiliation: Department of Food Science and Biotechnology, Kyungsung University, Busan 608-736, South Korea.
authors.forename: Hwan Hee
authors.initials: HH
authors.lastname: Park
authors.forename: Natania
authors.initials: N
authors.lastname: Kam
authors.forename: Eun Yeol
authors.initials: EY
authors.lastname: Lee
authors.forename: Hee Sook
authors.initials: HS
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D015151:Immunoblotting; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011133:Polysaccharide-Lyases / Q000235:genetics*; D017422:Sequence Analysis, DNA; D020578:Sphingomonas / Q000201:enzymology* / Q000235:genetics; D013696:Temperature
chemical_list: D017931:DNA Primers; D004275:DNA, Ribosomal; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase