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We report a glycoside hydrolase (GH)-118 β-agarase from a strain of Agarivorans, in which we previously reported recombinant expression and characterization of the GH-50 β-agarase. The GH comprised an open reading frame of 1,437 base pairs, which encoded a protein of 52,580daltons consisting of 478 amino acid residues. Assessment of the entire sequence showed that the enzyme had 97%nucleotide and 99% amino acid sequence similarities to those of GH-118 β-agarase from Pseudoalteromonas sp. CY24, which belongs to a different order within the same class. The gene corresponding to a mature protein of 440amino acids was inserted, recombinantly expressed in Escherichia coli, and purified to homogeneity with affinity chromatography. It had maximal activity at 35oC and pH 7.0 and had 208.1 units/mg in the presence of 300 mM NaCl and 1 mM CaCl2. More than 80% activity was maintained after 2 h exposure to 35oC; however, < 40%activity remained at 45oC. The enzyme hydrolyzed agarose to yield neoagarooctaose as the main product. This enzyme could be useful for industrial production of functional neoagarooligosaccharides.