Active bacterial luciferase from a fused gene: expression of a Vibrio harveyi luxAB translational fusion in bacteria, yeast and plant cells.

The luxA and luxB genes encoding the luciferase from Vibrio harvey were fused by site-directed mutagenesis so that one polypeptide was encoded by the fused gene. The fused gene facilitated light production in Escherichia coli, Saccharomyces cerevisiae, and Nicotiana plumbaginifolia when the substrates decanal and reduced flavin mononucleotide were present. The specific activity of the encoded enzyme is not known. In E. coli and S. cerevisiae cells the light emission could be measured in viable, intact cells. The luxAB fusion provides a simple reporter gene for in vivo measurement of promoter strength in these species and may be useful in other systems as well.