Protoplast
Fusion - A method by which recombinants can be obtained in bacteria in which transformation with DNA is not possible, is now available. For example, in B. megaterium, recombinants have been obtained by the technique of protoplast fusion. In this process, two genetically distinct strains are mixed and protoplasted together with the use of lysozyme and then fused in the presence of polyethylene glycol.
The fused protoplasts are then allowed to grow into vegetative cells. Recombination occurs within the transient diploid protoplasts, which is followed by segregation and haploidization. The frequency of obtaining recombinants by this technique in B. megaterium is about 10-7 to 10-8 per bacterium and it appears to be a useful method to bring about recombination among bacteria in which other mechanisms of genetic exchange are not yet known.
