Quantify phage Phage are mixed with and adsorb to bacterial cellls )Dilute the mix > Add dilutions to"soft agar(contain many uninfected bacterial cells) > Poured onto a hard agar base >Incubated to allow bacterial growth and phage infection
Quantify phage ➢Phage are mixed with and adsorb to bacterial cells. ➢Dilute the mix. ➢Add dilutions to “soft agar” (contain many uninfected bacterial cells). ➢Poured onto a hard agar base. ➢Incubated to allow bacterial growth and phage infection
PHAGE DILUTION SERIES PHAGE 1/10 l/100 l/1000 PHAGEPHAGE PHAGE Copyright 2004 Pearson Education, Inc, publishing as Benjamin Cummings -Softagar ← Hard agar a petri dish
Soft agar Hard agar a petri dish
As the viruses ③ replicate and are released, they spread and infect the nearby cells. This circle-of-death produces a hole or PLaQUE in a lawn of living cells. These plaques can be easily seen and counted so that the numbers of virus can be quantitated
This circle-of-death produces a hole or PLAQUE in a lawn of living cells. These plaques can be easily seen and counted so that the numbers of virus can be quantitated. As the viruses replicate and are released, they spread and infect the nearby cells
The Single-Step Growth Curve Latent period- the time lapse between infection and burst release of sIze progeny. Burst size-the number of phage released latent period time Figure 21-4
The Single-Step Growth Curve Bacteriophage Figure 21-4 Latent periodthe time lapse between infection and release of progeny. Burst size-the number of phage released
The single-Step Growth Curve >It reveals the life cycle of a typical lytic phage. >It reveals the length of time it takes a phage to undergo one round of lytic growth, and also the number of progeny phage produced per infected cell
The Single-Step Growth Curve ➢It reveals the life cycle of a typical lytic phage. ➢It reveals the length of time it takes a phage to undergo one round of lytic growth, and also the number of progeny phage produced per infected cell