Co-induction of fatty acid reductase and luciferase during development of bacterial bioluminescence.

The luminescent bacterium Photobacterium phosphoreum has been shown to possess a fatty acid reductase based on the stimulation of the aldehyde-dependent luminescent reaction on incubation of the enzyme with ATP, NADPH, and tetradecanoic acid (Riendeau, D., and Meighen, E. (1979) J. Biol. Chem. 254, 7488-7490). A direct, luciferase-independent assay for the fatty acid reductase has now been developed using [3H]tetradecanoic acid as substrate and thin layer chromatography to separate and identify the products of the reaction. Tritiated aldehyde was the only product of the reaction at early times of assay, and the amount produced was linearly dependent on time and extract concentration. The labeled aldehyde was further reduced to alcohol after prolonged incubation, indicating that long chain aldehyde reductase(s) are also present in bioluminescet bacteria. Measurement of the fatty acid reductase activity in extracts during growth and development of the bioluminescent bacteria showed that the fatty acid reductase activity is co-induced with luciferase, suggesting that these enzymes are coordinately regulated and directly implicating the fatty acid reductase in aldehyde biosynthesis in the bacterial bioluminescent system.