Purification and Properties of an Extracellular Agarase from Alteromonas sp. Strain C-1

A marine bacterial strain isolated from the Bay of San Vicente, Chile, was identified as Alteromonas sp. strain C-1. In the presence of agar, this strain produced high levels of an extracellular agarase. The production of agarase was repressed by glucose, with a parallel decrease in bacterial growth. The enzyme was purified to homogeneity by anion-exchange chromatography and gel filtration, with an overall yield of 45%. The enzyme has a molecular weight of 52,000, is salt sensitive, and hydrolyzes agar, yielding neoagarotetraose as the main product, with an optimum pH of about 6.5.