Escherichia Coli, more commonly known as E. coli, is a bacteria that can be found in the large intestine of warm-blooded organisms. It can be totally harmless, and in some cases helpful by producing vitamin K. However, there are also many other cases where E. coli can be a harmful bacteria, and in some cases even lethal. Harmful E. coli usually only causes mild disease in humans, but it can be life threatening to children, the elderly, and immunocompromised people.
E. coli is a fairly simple structured bacteria. It is a bascillus bacteria meaning that it is rod-shaped (see the picture to the right). The inner part of the cell contains cytoplasm, and in the cytoplasm DNA is stored. There is a cell membrane that surrounds the inner components of the cell, and many, but not all E. coli bacteria have a flagellum.There are many different strains of E. coli, some harmful and some harmless. Each strain is different in it's characteristics. There are many different strains of E. coli because E. coli is strongly drug resistant and is constantly evolving to avoid the antibiotics that are used to try and fight it (such as streptomycin or gentamicin.) The strong drug resistance of E. coli can make it hard to fight, but when diagnosed early on, there are many existing drugs that can identify, locate, and exterminate the harmful strains of E. coli in you. E. coli can cause a variety of diseases, and also a wide range of severity of these diseases depending on age, immune system effectiveness, how early it is diagnosed, and how well and properly it is treated.
Sources:
http://en.wikipedia.org/wiki/Escherichia_coli
http://www.lbl.gov/Publications/Currents/Archive/Mar-05-2004.html
http://science.howstuffworks.com/environmental/life/cellular-microscopic/cell1.htm
