What is E. coli? Ans. E. coli is a Gram-negative rod-shaped bacterium that is typically around 1 μm long and 0.35 μ m wide. It is able to survive with or without oxygen and thus is a "facultative aerobe". Although it is able to grow fast without forming clumps in various inexpensive chemically defined media, it is not typically tolerant to very high or low temperatures or extreme acidity/alkalinity. Its potential for fast growth, the number of molecular techniques for genetic manipulations available, and a good amount of knowledge about its genetics mean that it has the versatility to be utilized in many ways. Also, E. coli mainly replicates asexually, meaning that modifications made to the genome are maintained and thus effects seen in these mutants are reproducible. These factors make E. coli a good model organism for molecular genetics. E. Coli Symptoms Ans. Symptoms of E. coli typically set in within 2-3 days of infection. Symptoms ...