Is Escherichia coli pathogenic?

Actually, this is a very good question. When we look at the definition of pathogenic, we know that disease causing microorganism are pathogenic. Is E.Coli a disease causing microorganism? Well, E .coli can be found in uncooked foods, feces and in other unsanitary conditions. If the E.coli found in any of these conditions are consumed, we have a very serious problem. However, what about the E.coli that is inside of our large intestine helping synthesize vitamin K. These guys are not pathogenic. When answering questions of whether bacteria are pathogenic we must always consider the strain. The strain tells us the pathogenic status of the bacteria and will even tell us the degree of pathogenicity.