Process steps of phage isolation

Sample collection: The first step in phage isolation is to collect the sample from the natural environment, which is believed to contain phages. The sample could be soil, water, or any other organic material.

Sample preparation: The collected sample needs to be prepared to isolate the phages. The preparation process involves filtering the sample to remove any large debris, centrifuging to concentrate the phages, and adding a buffer solution to stabilize the phages.

Inoculation: The prepared sample is then inoculated onto a bacterial culture plate, which has a layer of agar. The bacterial culture used for inoculation should be susceptible to the phages present in the sample.

Incubation: The inoculated bacterial culture plate is then incubated at optimal temperature and conditions to allow the phages to infect the bacterial cells.

Plaque formation: After incubation, the phages infect the bacterial cells, resulting in the formation of plaques on the bacterial culture plate. Each plaque represents a single phage particle that has infected and lysed a bacterial cell.

Plaque purification: Purification of the phages is done by picking a single plaque from the bacterial culture plate and transferring it to another culture plate for further growth. This process is repeated multiple times to ensure that the phage is pure and free from any bacterial contamination.

Characterization: Once the phage is purified, it is characterized by determining its morphology, host range, and other properties. The characterization helps in identifying the phage and understanding its potential applications.