Genetic techniques appropriate for the biotechnological exploitation of cyanobacteria

A large collection of genetic tools are available for those who wish to manipulate laboratory strains of cyanobacteria. These tools have not yet been applied to strains that might be used for more practical ends. Applications in which a natural ability of a cyanobacterial strain is exploited would require different genetic tools than those in which a cyanobacterial strain is called upon to produce a foreign product. DNA can be transferred into cyanobacteria by three methods: transformation, conjugation, and electroporation. With each, efficiency is greatly affected by restriction enzymes within the recipient cyanobacterium. Transferred DNA may be propagated in the recipient strain if carried on a replicating plasmid or if integrated into the host chromosome. Different means of integration offer different advantages. Methods are available to increase and control the expression of genes of interest. These genetic tools are discussed with reference to specific problems that might be faced in the exploitation of cyanobacteria.