Structure of E. coli bacteria.
Shape: minute and rod like
Size: Length, 2 – 4 m; width, 0.5-1 m
1) They are gram negative, ie they lose their colour when they are washed with sprit after their being colored with violate crystal iodine.
2) They may be flagellated or non-Flagellated. Flagellated bacteria can move while non- flagellated bavteria cannot move.
3) They base plasmid. Plasmid is present additionaly as a circular D.N.A. other than nucleotide.
4) In their cell membrane pili is present
5) From the characteristics mentioned above it is seen that E. coli bacteria are more or less identical to the common bacteria.
They usually live in the intestines of vertebrates including human, A great deal of E coli bacteria come out with the fecal matter of the animal and can exist in water, soil and in food materials.