Thread: viral selectivity

im going to be conducting an experiment using bacteriophages but i need to know how phages and viruses select the cell that they are going to infect. certain viruses will only infect certain cells. what makes this so? is there a chemical attration? a simiilarity in shape? i haven't been able to find the answer anywhere.

THe first step of infection is purely mechanical- virus and cells have to get into proximity, which is less trivial then it sounds. With bacteria it shouldn't be a problem though. The next step will be virus binding to receptors on the cell surface- if the cell doesn't have the relevant receptor the virus won't get anywhere.