Microbiology Notes | Biochemistry,Immunolgy,Cell biology

Definition Bacterial Transformation is a processes in which a bacterial cell intake a segment of DNA from the environment or other bacteria,and get integrated with it by homologous recombination. Transformation in bacteria was first demonstrated in 1928 by the British bacteriologist Frederick Griffith. IN 1944  Oswald Avery, Colin MacLeod, and Maclyn McCarty experimentally proved that DNA is the main principle involve in gene transformation. Classification Transformation is classified into two classes,this are- Natural Transformation Artificial Transformation. Natural Transformation: Some bacteria can naturally transformable they can take DNA From environment without any special treatment Artificial Transformation: Most of the bacteria are not natural transformable. These bacteria can be made competence by certain chemical treatment or by strong electrical shock. Mechanism of Transformation The transformation mechanism first obser...

In 1928 Frederick Griffith experimentally proved that the bacterial cells are transfer their gen through a processes which is called Transformstion. For his experiment he took two different strains of Diplococcus pneumoniae and inject them into a mice.The two different strains are- S – III Strain (Smooth,capsulated,virulent) R – II Strain (Rough,uncapsulated,Nonvirulent). PROCESSES At first he applied the S-III strain or virulent strain on mice the mice is died. After that he applied the R-II strain on mice,the mice is not effected because of its not a virulent strain it don’t contain capsule. Then he heat killed the S-III strain to destroy their virulent properties, and injected them into a mice.a a result the mice is not effected by the heat killed S-III strain.