Cloning vectors derived from bacterial plasmids

A wide variety of plasmid cloning vectors, most of which utilize the basic Co1E1I replicon have been constructed. Utilizing these vectors, in conjunction with the newly developed techniques of gene isolation and oligonucleotide synthesis, essentially any gene which can be identified can be cloned. We anticipate that future work in this area will be directed at improving techniques for the regulated expression of cloned genes and the further development of plasmid replicons in which the copy number can be readily controlled.