For the second time in a week I note the passing of an important virologist. Renato Dulbecco, together with David Baltimore and Howard Temin, received the 1975 Nobel Prize in Physiology or Medicine for discoveries about how tumor viruses interact with the genetic material of the cell. Dulbecco also devised my favorite virological method, the plaque …
There is an excellent question in the comments to “Are all virus particles infectious?“: if the particle-to-PFU ratio for a virus stock is 10,000:1, and I infect 1,000,000 cells with 10,000 particles, how many plaques would I expect to observe? Answering this question provides insight into the particle-to-PFU ratio of viruses. If we take 10,000 particles …
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. If ten million virions are added, the MOI is ten. Add 100,000 virions, and the MOI …
One of the most important procedures in virology is measuring the virus titer €“ the concentration of viruses in a sample. A widely used approach for determining the quantity of infectious virus is the plaque assay. In this technique, the spread of progeny viruses released by individually infected cells is restricted to neighboring cells by …
If you have been following the results of my experiments on inhibition of rhinovirus replication by ZnCl2, you know that I’ve been trying to determine why concentrations of the salt higher than 0.1 mM are toxic to HeLa cells. I have found that 0.1 mM ZnCl2 does inhibit rhinovirus plaque formation but not sufficiently to …
Rhinovirus and zinc part 5: Magnesium is not the culprit Read More »
Recently I began experiments to understand how zinc inhibits rhinovirus replication, and I promised to document my findings on the pages of this blog. Here are the results of the second plaque assay. In the last experiment I confirmed the finding that 0.1 mM ZnCl2 inhibits plaque formation by rhinovirus type 1A. Based on the …
