Cloning, Expression, and Characterization of a Cold-Adapted and Surfactant-Stable Alginate Lyase from Marine Bacterium Agarivorans sp L11

The purpose of this study was to find a cold-adapted and surfactant-stable alginate lyase as a candidate for biotechnological and industrial applications. The gene for a new alginate lyase, AlyL1, from Agarivorans sp. L11 was cloned and expressed in Escherichia coli. The recombinant AlyL1 was most active at 40 degrees C (1,370 U/mg). It was a cold-adapted alginate lyase, which showed 54.5% and 72.1% of maximum activity at 15 degrees C and 20 degrees C, respectively. AlyL1 was an alkaliphilic enzyme and most active at pH 8.6. In addition, it showed high stability in the presence of various surfactants at a high concentration (from 0.1% to 1% (w/v)). AlyL1 was an endo-type alginate lyase that degraded both polyM and polyG blocks, yielding disaccharides and trisaccharides as the main products. This is the first report of the cloning and functional expression of a cold-adapted and surfactant-stable alginate lyase. AlyL1 might be an interesting candidate for biotechnological and industrial applications.