Question

Describe a method one can use to culture these lambda and M13 phage particles into large numbers.

Answer 1

The strategies for the scale-up of lambaphage and M13 growth and primary downstream purification are still in their infancy, but we the amount of phage that needs to be added to large-scale growth volumes can be reduced by several orders of magnitude from what is common at the lab scale. Phage can be added directly to fermenters where rapidly stirring impellers are needed to maintain aeration and correct physiology of the host with no cessation of the stirring, and the phage will find their host and attach with no difficulty. The use of cells engineered to produce their own broad-spectrum periplasmic nuclease gives significant gains in the destruction of host DNA and RNA release on lysis, and this prevents the contamination of the phage with nucleic acid when the phages are concentrated by precipitation. The gentle precipitation method of using low concentrations of PEG can then be used to give relatively pure preparations of phage in one step. These methods can be used together and will allow the large-scale uses of phage in the future in medical and clinical applications and then beyond into biotechnological applications such as the uses of filamentous phage in electronics like phage batteries and the phage laser.