Characterization and purification of starch-degrading enzymes from a marine bacterium

A mesophilic marine bacterium was isolated from a fringe mangrove on the south coast of Puerto Rico. This gram negative, facultatively anaerobic bacterium was identified by 16S rRNA and biochemical tests as Vibrio sp. This bacterium had the ability of starch degradation and utilized starch as sole source of carbon. Characterization studies of starch-degrading enzymes of this organism showed the presence of an active alpha-amylase, an alpha-glucosidase and a pullulanase. Enzyme activity was detected extracellular and intracellular. Purification of these enzymes offered an opportunity of studying a novel marine enzymatic system and the initial development of potentially salt-tolerant enzymes. Fast Protein Liquid Chromatography (FPLC) was used to separate proteins involved in starch-degradation. Activity is associated to multiple protein bands in a native gel. More research is necessary to determine if this enzymatic system consists of multiple proteins acting in concert on the same substrate.