Cloning, expression, and characterization of a glycoside hydrolase family 118 beta-agarase from Agarivorans sp. JA-1

J Microbiol Biotechnol. 2012 Dec;22(12):1692-7. doi: 10.4014/jmb.1209.09033.

Abstract

We report a glycoside hydrolase (GH)-118 beta-agarase from a strain of Agarivorans, in which we previously reported recombinant expression and characterization of the GH- 50 beta-agarase. The GH comprised an open reading frame of 1,437 base pairs, which encoded a protein of 52,580 daltons 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 beta-agarase from Pseudoalteromonas sp. CY24, which belongs to a different order within the same class. The gene corresponding to a mature protein of 440 amino acids was inserted, recombinantly expressed in Escherichia coli, and purified to homogeneity with affinity chromatography. It had maximal activity at 35 degrees C 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 35 degrees C; however, < 40% activity remained at 45 degrees C. The enzyme hydrolyzed agarose to yield neoagarooctaose as the main product. This enzyme could be useful for industrial production of functional neoagarooligosaccharides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alteromonadaceae / enzymology*
  • Alteromonadaceae / genetics
  • Bacterial Proteins / biosynthesis*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Chromatography, Thin Layer
  • Cloning, Molecular
  • Enzyme Stability
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Glycoside Hydrolases / biosynthesis*
  • Glycoside Hydrolases / chemistry
  • Glycoside Hydrolases / genetics
  • Hydrogen-Ion Concentration
  • Hydrolysis
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Sepharose / metabolism
  • Temperature

Substances

  • Bacterial Proteins
  • Recombinant Proteins
  • Sepharose
  • Glycoside Hydrolases
  • agarase