How do human diseases relate to gram-negative and gram-positive diseases? Simple answers plz! 10 pts b.a?
J-LEW
Please keep your answer as simple as possible, I am new to bacteria and viruses and such, and need help.
Best answer gets 10 points! Thank you very much
I assume you know or already have a background on the cell membrane structure of Gram negative and Gram positive bacteria, in that, basically, the former does not have an intact cell wall while the latter does not have a lipopolysaccharide (LPS) nor a periplasmic layer. Pretty much, going by that information alone can somehow provide an explanation to your inquiry about how such bacterial organisms, and bacteria in general, can cause diseases.
Scientists believe that Gram negative bacteria have more potential to cause a disease compared to Gram positive bacteria, mainly because of the fact that only Gram negative organisms have LPS. And LPS, as you may know, is a virulence factor for Gram neg. bacteria, allowing them to by-pass the body’s immune system and thereby cause a disease; such are also not susceptible to lysozyme, the enzyme responsible for the breakdown of Gram positive cell wall, again allowing them to roam freely in the body. So, the longer they can spend time in the body, the greater the chance that they would initiate a systemic infection and elicit a full blown manifestation of a disease. A simple example is Neisseria meningitidis, the etiologic agent of Epidemic Spinal Meningitis; it is a Gram(-) bacterium that has a lethal LPS that can cause shock when there is bacteremia (bacteria in the blood), and meningitis when it gets to the spinal column of humans.
But Gram(+) bacteria, although vulnerable to lysozyme, are also clever enough to “fool” the immune system so they, too, can cause a disease. A good example is Staphylococcus aureus–the “Staph infection” agent–which coats itself with a blood clot to prevent its ingestion by neutrophils or active macrophages, thus allowing them to survive in our body and possible initiate a systemic disease.
There are others as well, including toxins that are released by bacterial organisms that, even without the bacterium, can cause a disease by itself–in essence, a “stand alone” disease agent. And various Gram(+) and (-) release toxins, like the Shiga toxin derivative of Escherichia coli in food poisoning and the Toxic Shock Syndrome Toxin 1 of S. aureus in Toxic Shock Syndrome.
Viruses, as opposed to bacteria, have a different route of pathophysiology, and have a different range of effects on the host, with humans of no exception of course. In any case, they do cause nasty diseases, and can be a handful to treat.
Well, this is as elementary as I can get when it comes to the relation of cell membrane component and diseases. I hope this helps you in some ways!