Experiment on the bacterium Escherichia coli - Coursework Example

Escherichia coli (E.coli) are gram negative, non-spore forming strains of bacterium that usually inhabit the intestinal tracts of humans and other warm-blooded animals. They are facultative anaerobes that ferment simple sugars like glucose into lactic, acetic and formic acids (HITM, 2006). Most E coli strains are harmless and even are beneficial in the sense that they assist the host by destroying other harmful strains of bacterium and by synthesising sizeable amounts of vitamins (HITM, 2006).

Nevertheless, there are certain strains of E coli that prove harmful to humans and other hosts. These are categorised into four major groups - enteropathogenic E coli, enetroinvasive E coli and enterohemorrhagic E coli (HITM, 2006). These four harmful categories earn the E coli strain significant ill-repute as one of the most significant foodborne pathogens. In recent years great attention is being placed on successfully combating their pathogenic influence on humans. An estimate of this harmful influence can be derived from the fact that approximately 73,000 cases of human illnesses, inclusive of 63 deaths per year, in the United States were caused by the bacterium O157:H7 (Mead et al., 1999), a viciously enterohemorrhagic E coli strain.

It is notable that this is one of the many harmful strains that are pathologically sensitive to humans. All organisms require a benign environment to exist and propagate themselves. Thus, they seek out such environments where they have sufficient food for sourcing their energy needs for the metabolic and biosynthetic tasks. There are several factors that influence the benign environment in which E coli strains, including and especially the harmful ones, can successfully thrive. Since humans are plagued by these harmful strains it is logical that they continuously seek out ways and means by which they can alter these favourable environmental conditions and disallow these bacteria to survive and propagate.

This research study is one such wherein two environmental conditions - temperature and Bacteria can be grown in the laboratory in culture media that are designed to provide all the essential nutrients in solution for bacterial growth. In this investigation the media types Luria Bertani (LB) broths and Nutrient broths will be utilised to investigate thermal conditions under which two strains of E coli - (a common experimental strain) and CU1 - thrive. The two E.coli strains will be grown in