FIG. 3.

Genetic complementation of the aliphatic-aldehyde deficiency in wild-type V. salmonicida. (A) The plasmid used for complementation studies, pEN135, contains the V. fischeri ES114 AAS genes, luxCDE, as well as the luciferase subunit gene luxB. The other luciferase subunit gene, luxA, is deleted, and luxG (gray) is inactivated by a transposon insertion (triangle). MCS, multiple cloning site. (B) Comparison of luminescence produced by wild-type V. salmonicida harboring the vector plasmid pVO8 and that produced by wild-type V. salmonicida harboring the AAS gene-carrying plasmid pEN135. Aliquots of cultures (late exponential phase of growth; OD at 600 nm, 0.7 to 0.9) were either immediately measured photometrically or supplemented with aliphatic aldehyde before measurement. The dashed line represents the limit of photometric detection. Data shown are representative of the results of three independent experiments.