EXPRESSION OF THE ALCALIGENES-EUTROPHUS PHBA GENE IN ESCHERICHIA-COLIUSING A POSITIVE SELECTION VECTOR BASED ON PHAGE-LAMBDA LYSIS GENES

A new Positive selection vector, pGS23, based on the Lambda lysis cass ette has been designed for efficient expression of homologous and hete rologous genes in Escherichia coli. The plasmid permits controlled exp ression of a gene of interest under transcriptional control of the lac promoter with translation initiation of coding sequences directed by the phage T7 gene 10 ribosome binding site, The application of the vec tor system was tested for high level expression of the heterologous ph bA gene of Alcaligenes eutrophus in E. coli.