LUXAB GENE FUSIONS WITH THE ARSENIC AND CADMIUM RESISTANCE OPERONS OFSTAPHYLOCOCCUS-AUREUS PLASMID-PI258

pC101, a novel shuttle vector between Escherichia coli and Staphylococ cus aureus carrying the lux genes encoding luciferase from Vibrio harv eyi, selectable ampicillin and chloramphenicol markers and origins of replication for Gram-negative and Gram-positive bacteria has been cons tructed. The inducibility of the arsenic and cadmium operon from S. au reus plasmid pI258 to different ions has been tested in E. coli and in S. aureus with two fusions in pC101: an arsB-luxAB and a cadA-luxAB t ranscriptional gene fusion. Patterns of induction are influenced by th e host strain and are slightly different from previous reports using t he blaZ gene as reporter gene.