question on viruses

[the guy]

is it possible for a virus to have two different types of receptor-binding protein and so be able to infect two different types of cell?

[CharonY]

It depends on the mode of host-virus interaction. However, receptor binding is not necessarily 100% specific in any case (as most receptor-ligand binding reactions). Thus a virus does not necessarily need a specific protein for each cell type to be invaded. Note that in most cases one would only classify the receptor on the host's cell surface as a receptor. Parts of the viral envelope that bind to it are often termed by their more general function. E.g. one would say that the viral glycoprotein XY binds to the cognate host receptor. Or one would mention the specificity of the envelope protein XY to the whatever-receptor (i.e. the normal function of the receptor outside the unintended virus-binding) of the host.

Edited November 14, 2011 by CharonY

[Greg Boyles]

It depends on the mode of host-virus interaction. However, receptor binding is not necessarily 100% specific in any case (as most receptor-ligand binding reactions). Thus a virus does not necessarily need a specific protein for each cell type to be invaded. Note that in most cases one would only classify the receptor on the host's cell surface as a receptor. Parts of the viral envelope that bind to it are often termed by their more general function. E.g. one would say that the viral glycoprotein XY binds to the cognate host receptor. Or one would mention the specificity of the envelope protein XY to the whatever-receptor (i.e. the normal function of the receptor outside the unintended virus-binding) of the host.

 

 

From memory the AIDS virus lipid coated and its pentration into the cells is at least partly a result of the virus 'dissolving' its way through the cell membrane.

 

Is that correct?

[CharonY]

The envelope of HIV (which is recognized by receptors) are glycoproteins. Upon binding to their respective receptors, fusion and entry events (mainly at the plasma membrane, but potentially also with endosomes) occur. So, the recognition zone is defined by the proteins, however the bilayer is important for the fusion event.