ESCHERIACJIA COLI

E.Coli is normally present in the intestinal tract of humans and animals but they are also present in the water and soil. They gram negative bacteria present in the form of rods. They are mostly motile except some strains. E.coli is non spore forming bacteria. (Monica2000)

1.3.1:Cultural Characteristics include:

1)      Facultative Anaerobes

2)      Optimum temperature for growth :  

  i.      35 to 37°C.

3)      On blood agar:

  i.      1-4 mm calonies , round , having entire edge.

4)      Some strains hemolytic

5)      On MacConkey agar :

  i.      Ferment lactose

ii.      Pink calonies(Figure1)

iii.      Some strains non motile and non lactose fermentors.