In a series of experiments with Streptococcus and mice F. Griffith concluded that
R-strain bacteria had been transformed. Explain.
1. Griffith experimented with Streptococcus Pnuemoniae, a bacterium that causes
pneumonia on bacterial transformation.
2. There are two different strains of this bacterium, one forming smooth colonies
protected by a polysaccharide coat (S-Strain) and the other forming rough colonies
3. The S-strain bacteria are virulent and the R-strain bacteria are non-virulent i.e.
they do not cause disease.
4. He injected live R-strain bacteria into mice, the mice did not die.
5. He injected live S-strain bacteria into mice, they died due to pneumonia.
6. The mice injected with heat killed S-strain bacteria survived.