Bacteria, Viruses and Prions Essay example

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We’ve all heard of viruses, bacteria and the diseases they can harm us with, but many of us haven’t even heard of prions and most people probably don’t know specific details about viruses or even bacteria for that matter. They’re all very interesting forms of organic matter, though. Bacteria are the only one of the three that are actually considered life forms 100%. The topic of whether or not viruses are to be considered an organism is very debatable in the world of microbiology, because they don’t actually have even a single cell, but they reproduce and have many other things in common with organisms. Prions on the other hand aren’t considered to be living at all, because all they are are malformed proteins that usually cause …show more content…
The capsids are usually very many-sided polyhedrons, they are considered to be quasi-spherical (as close to being spherical as it can be without actually being a sphere). Most viruses also have a type of receptor in order to attach itself to a host cell and inject its genetic information inside of it. These receptors are usually host specific, so they can only attach to one type of cell. Some viruses have a viral envelope, which works to keep the virus protected and can help it to enter a cell directly through endocytosis. While viruses and bacteria are proteins, prions are proteins. Like their normal protein brothers and sisters, they’re made up of amino acids. The disease causing protein is called, PrP-res, and the normal one is called, PrP-sen. While they’re made of the exact same string of amino acids, the two forms have very different shapes. PrP-sen is produced by healthy cells, and the “sen” stands for “sensitive” because it is sensitive to being broken down, PrP-sen is found most frequently in the neurons of the brain. For some reason the shape of PrP-res completely changes its behavior and when it’s shaped in this way it is resistant to being broken down. Even though the structure of a prion is extremely simple, explaining it in a way that makes sense is complicated. All of these things have to reproduce in order to keep helping

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