High copy number self-replicating plasmids in pseudomonas

PseudomonasProvided herein are improved copy number plasmids, particularly those plasmids capable of replication in a bacterial cell. The improved copy number plasmid contain a deletion, insertion, or substitution in the replication control region, particularly a -specific replication control region, that results in an increase in plasmid copy number in comparison to a control plasmid. Also provided are host cells containing the improved copy number plasmids, as well as methods of using the improved copy number plasmids for the recombinant production of a protein of interest. Further provided are methods for generating plasmids with improved copy number. The methods disclosed herein involve the reiterative selection of improved copy number plasmids by the growth and selection of plasmids capable of growth under increasing selective pressure, wherein the selective pressure is applied utilizing a selection agent to which the control plasmid confers resistance.