A broad-host-range expression vector series including a Ptac test plasmid and its application in the expression of the dod gene of Serratia marcescens (coding for ribulose-5-phosphate 3-epimerase) in Pseudomonas stutzeri.

A series of expression vectors for gram-negative bacteria was constructed which combine broad-host-range, inducible expression from the tac promoter and diverse antibiotic resistance determinants. The tac promoter activity and the repression by lacIq can be quantitated with a separate test plasmid in the strain to be studied. The dod gene of Serratia marcescens was expressed in Pseudomonas stutzeri and was shown to code for D-ribulose-5-phosphate 3-epimerase.