title: Cloning, expression, and characterization of a glycoside hydrolase family 50 beta-agarase from a marine Agarivorans isolate.
abstract: The gene for a thermostable beta-agarase from Agarivorans sp. JA-1 was cloned and sequenced. It comprised an open reading frame of 2,988 base pairs, which encode a protein of 109,450 daltons consisting of 995 amino acid residues. A comparison of the entire sequence showed that the enzyme has 98.8% sequence similarities to beta-agarase from Vibrio sp. JT1070, indicating that it belongs to the family glycoside hydrolase (GH)-50. The gene corresponding to a mature protein of 976 amino acids was inserted and expressed in Escherichia coli. The recombinant beta-agarase was purified to homogeneity. It had maximal activity at 40 degrees C and pH 8.0 in the presence of 1 mM NaCl and 1 mM CaCl(2). The enzyme hydrolyzed agarose as well as neoagarohexaose and neoagarotetraose to yield neoagarobiose as the main product. Thus, the enzyme would be useful for the industrial production of neoagarobiose.
authors.affiliation: Department of Pharmaceutical Engineering, College of Medical Life Sciences, Silla University, Busan, Korea.
authors.forename: Dong-Geun
authors.initials: DG
authors.lastname: Lee
authors.forename: Geun-Tae
authors.initials: GT
authors.lastname: Park
authors.forename: Nam Young
authors.initials: NY
authors.lastname: Kim
authors.forename: Eo-Jin
authors.initials: EJ
authors.lastname: Lee
authors.forename: Min Kyung
authors.initials: MK
authors.lastname: Jang
authors.forename: Young Gyun
authors.initials: YG
authors.lastname: Shin
authors.forename: Gwang-Seok
authors.initials: GS
authors.lastname: Park
authors.forename: Tae-Min
authors.initials: TM
authors.lastname: Kim
authors.forename: Jae-Hwa
authors.initials: JH
authors.lastname: Lee
authors.forename: Jung-Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Sang-Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Sang-Hyeon
authors.initials: SH
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D006026:Glycoside Hydrolases / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D020560:Proteobacteria / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry; D017422:Sequence Analysis, DNA; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D011994:Recombinant Proteins; D006026:Glycoside Hydrolases; C019624:agarase