In this article we will discuss about the history of bacteriophages. In 1896, for the first time, Ernest Hankin (a British bacteriologist) reported for the presence of antibacterial activity (against Vibrio cholerae) in the waters of the Ganges and Yamuna rivers in India. He suggested that an unidentified substance (which passed through fine porcelain filters and was heat labile) was [...]
In this article we will discuss about the bacteriophage typing of various serotypes. 1. Bacteriophage Typing of S. typhi: This is done by determining the sensitivity of the culture to a series of variants of a single phage, Vi-phage II, which have been adapted to the different types of typhoid bacillus. In 1938, Craigie and Yen developed the first Vi-phage-typing [...]
In this article we will discuss about:- 1. Morphology of Phage Lambda 2. DNA and Gene Organization of Phage Lambda 3. Life Cycles of Phage Lambda 4. Genetic Map of Phage Lambda 5. Choice between Lytic and Lysogenic Cycles. Morphology of Phage Lambda: Morphological structure of phage λ is given in Fig. 18.11A. The head has 20 faces. A 20- [...]