The following points highlight the 3 modes of gene transfer and genetic recombination in germs. The modes are: 1. Transformation 2. Transduction 3. Bacterial Conjugation.
Mode no. 1. Change:
Historically, the development of change in germs preceded one other two modes of gene transfer. The experiments carried out by Frederick Griffith in 1928 suggested when it comes to very first time that a gene-controlled character, viz. Formation of capsule in pneumococci, could possibly be utilized in a variety that is non-capsulated of germs. The transformation experiments with pneumococci fundamentally generated a similarly significant finding that genes are constructed with DNA.
In these experiments, Griffith utilized two strains of pneumococci (Streptococcus pneumoniae): one by having a polysaccharide capsule creating ‘smooth’ colonies (S-type) on agar dishes that was pathogenic. One other stress had been without capsule creating that is‘rough (R-type) and ended up being non-pathogenic. Read more