Just a short post today. I give you, for the first time in medical history, a detailed inside look at Human Immunodeficiency Virus (HIV).
I have to admit, I had never thought to wonder how a virus might be structured... I always thought of them as a protein sheath with an attitude. But an ambitious team at Visual Science, led by Ivan Konstantinov, has created the most detailed 3D model of the virus to date by compiling information from over 100 studies in virology, as well as using X-ray analysis and NMR microscopy.
You might be wondering what the colors represent (if not simply for contrast). The orange colored sections represent material that are coded for by the virus’ own genome, while the gray is material assimilated into the virus from the host cells; these images illustrate the spatial configuration of 17 different proteins.
There are in fact 2 different ‘species’ of HIV: HIV-1 and HIV-2. I put species in quotations because although I personally consider viruses as a form of life (to which the term species would apply), there are those who do not... although I suppose in the most generic sense (not biological), you could refer to different types of particles as ‘species’. The HIV viron is between 100 and 180 nm in diameter, and is encased in a cell-derived lipid membrane composed of nearly 160,000 lipid molecules of 8 types in different proportions. Deep within, there is a cone-shaped capsid that contains two copies of positive single-stranded viral RNA. The HIV genome is approximately 10,000 nucleotides long, and contains 9 genes that code for 15 proteins.
There are in fact 2 different ‘species’ of HIV: HIV-1 and HIV-2. I put species in quotations because although I personally consider viruses as a form of life (to which the term species would apply), there are those who do not... although I suppose in the most generic sense (not biological), you could refer to different types of particles as ‘species’. The HIV viron is between 100 and 180 nm in diameter, and is encased in a cell-derived lipid membrane composed of nearly 160,000 lipid molecules of 8 types in different proportions. Deep within, there is a cone-shaped capsid that contains two copies of positive single-stranded viral RNA. The HIV genome is approximately 10,000 nucleotides long, and contains 9 genes that code for 15 proteins.
If you were interested in the names of a few viroid structures, watch this short video (no sound).
Now, as incredible as I find the detail in these images, I can't help but be a little creeped out. I mean, I understood how viruses reproduced, but I still had this mental image of a virus as an autonomous, discrete entity completely separate from the host. But now that simplistic view has been shattered now having seen exactly what the virus uses from the host cells, and frankly I’m the better for it. HIV AIDS (as I’m sure you're all aware) is a terrible disease with no known cure, and although we have access to medical treatments and support in developed nations, the developing world (most notable Africa) is just being devastated. But there is hope, in the form of an organized, strategic plan released in 2010 for the development of an HIV vaccine. We're not there yet, and we have a long way to go... but it’s not hopeless.
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