What is the one step growth curve?
One-step growth curves are used to make determinations about the life cycle of a virus on a particular host. By following a virus infection during one life cycle phase of host a growth curve can be constructed and the burst size can be calculated.
What is one step growth curve of bacteriophage?
The one-step multiplication curve for a bacteriophage population follows three steps: 1) inoculation, during which the virions attach to host cells; 2) eclipse, during which entry of the viral genome occurs; and 3) burst, when sufficient numbers of new virions are produced and emerge from the host cell.
How do you measure viral burst?
Calculating burst size..
- Take the FREE phage average of the time points on the plateau before the burst (A)
- Take the FREE phage average of the time points on the plateau after the burst (B)
- Subtract A from B; This is the total burst or new phages released (C)
Why is it called one-step growth curve?
During this phase, the infection, adsorption, injection and syntheses of new viral DNA and protein coat occur. The cycle can then start over with the infection of new cells. In this manner, the shape of the curve would look step-wise and that is why the process is called “one-step phage growth curve”.
Which broth is used in one-step growth curve for determination of virus titre?
Note: Depending on the host bacterial strain and the bacteriophage, a different a liquid medium may be more suitable for the initial culturing of the host bacterial strain or a different solid medium may be more suitable for subsequent growth. Lysogeny broth (LB) is used in this protocol for the broth and the agar.
What is MOI in virology?
Multiplicity of infection (MOI) is a frequently used term in virology which refers to the number of virions that are added per cell during infection. If one million virions are added to one million cells, the MOI is one.
How is burst length calculated?
What are the phases of the growth curve?
The stages of a typical growth curve (figure below) are: 1. Lag phase: When the cells are adjusting to their new environment. During this. phase, cellular metabolism is accelerated, resulting in rapid biosynthesis of. cellular macromolecules, primarily enzymes, in preparation for the next phase of. the cycle.
How to extrapolate growth curve using a ruler?
Using a ruler, extrapolate by drawing a line between each of the selected optical densities on the ordinate and the plotted line of the growth curve. Then draw perpendicular lines from these end points on the plotted line of the growth curve to their respective time intervals on the abscissa.
How to calculate the specific growth constant ( µ )?
Once you have determined the values of (Log10 N0) and (Log10 N1), the specific growth constant (µ) is then calculated using the formula: µ = Log10 N1 – Log10 N0/t1 – t0 Determination of Doubling Time “G”.
How is the growth curve used in microbiology?
Under these conditions, the cells will reproduce rapidly and the dynamics of the microbial growth can be charted by means of a population growth curve, which is constructed by plotting the increase in cell numbers versus time of incubation and can be used to delineate stages of the growth cycle.