title: Purification and characterization of an alkaliphilic alginate lyase AlgMytC from Saccharophagus sp. Myt-1.
abstract: In a previous study, we isolated and reported a second species of the Saccharophagus genus, Saccharophagus sp. strain Myt-1. In the present study, an alginate lyase gene (algMytC) from the genomic DNA of Myt-1 was cloned and characterized. The DNA sequence fragment obtained contained an open reading frame of 1,032 bp that encoded a protein of 343 amino acids with an estimated molecular mass of 37.6 kDa and a pI of 6.60. The deduced protein, AlgMytC, had the conserved amino acid sequences (RTELREM, QIH, YFKAGVYNQ) of the polysaccharide lyase family 7. A BLAST homology search indicated that AlgMytC shared an amino acid sequence identity of 95.9% with alg7A of S. degradans 2-40. The cloned and purified AlgMytC protein showed optimal activity at 40°C, and retained more than 90% of its total activity even after treatment at 25°C for 24 h. AlgMytC was very alkaliphilic with an optimal pH of 9.0, and more than 90% of its activity was retained in the pH range 8.5-10.0. Moreover, AlgMytC was stable over a wide pH range. The activity of AlgMytC was also stable in the presence of various detergents.
authors.affiliation: Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan. sakatoku@sci.u-toyama.ac.jp
authors.forename: Akihiro
authors.initials: A
authors.lastname: Sakatoku
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tanaka
authors.forename: Shogo
authors.initials: S
authors.lastname: Nakamura
mesh_terms: D034241:Alteromonadaceae / Q000201:enzymology* / Q000235:genetics; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames; D011133:Polysaccharide-Lyases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D004269:DNA, Bacterial; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase