Production of 4-methylumbelliferyl heptanoate hydrolase by Escherichia coli exposed to seawater.

The production of an enzyme, 4-methylumbelliferyl heptanoate hydrolase, in Escherichia coli exposed to enriched and nonenriched seawater was studied. In all media, except for seawater with no or very small amounts of organic material and seawater enriched with peptone, 4-methylumbelliferyl heptanoate hydrolase activity increased by 2 to 3 orders of magnitude within 2 days. Increased enzyme activity was assumed to be related to cells not undergoing lysis but adapting to conditions of nutrient limitation.