Proteolytic inactivation of the luciferase from the luminous marine bacterium Beneckea harveyi

The enzymatic activity of bacterial luciferase from Beneckea harveyi (a heterodimer, Mr = approximately 79,000) is rapidly lost upon treatment with trypsin or chymotrypsin. Under nondenaturing conditions, the proteolytically inactivated molecule has the same apparent molecular weight as the native enzyme, and appears to be relatively stable to further proteolytic degradation. Gel electrophoresis in sodium dodecyl sulfate of the products of this digestion shows that only the alpha subunit is degraded during the time of these experiments, and its rate of loss is the same as the rate of loss of light-producing activity. The action of either protease produces a species with mobility indicative of a molecular weight of about 28,000 and smaller fragments, and an unaltered beta subunit.