Visualization and Size Assessment of Faustovirus Using Electron Microscopy

Take a culture of amoeba infected with a giant virus known as the Faustovirus.

Collect the culture supernatant containing the Faustovirus.

On a glow-discharged electron microscopy grid, deposit the supernatant.

Incubate to allow the adsorption of viral particles onto the grid.

Blot the grid on filter paper to remove unbound viral particles.

Deposit a drop of ammonium molybdate.

Ammonium molybdate acts as a negative stain by binding to the grid around the virus and darkening the background to enhance contrast during imaging.

Remove excess ammonium molybdate by blotting the grid on filter paper.

Place the grid on a petri dish and allow it to dry.

Then, place the grid on the sample holder.

Introduce the holder into the electron microscope.

Capture an image of the Faustovirus and measure the size of the Faustovirus for further analysis.

To carry out electron microscopy, deposit five microliters of the positive sample onto a glow-discharged grid, and incubate at room temperature for approximately 20 minutes. Carefully dry the grid, then add a small amount of 1% ammonium molybdate and incubate for 10 seconds. After carefully removing the drop, allow the grid to dry for five minutes. Next, set the electron microscope to 200 kiloelectron volts. Then, place the grid on the holder and introduce the holder into the microscope. Click on the vacuum overview icon and check the vacuum. Then, close the valves, and set a spot size of five, and a magnification of 25,000 before beginning observation. After locating a giant virus on the acquisition screen, use the measure tool to measure the virus.

Carry out molecular biology and viral genome sequencing according to the text protocol.