This is because the structure of their cell wall is unable to retain the crystal violet stain so are colored only by the safranin counterstain. Examples of gram negative bacteria include enterobacter ...

and Clostridium turn purple with Gram stain. Other species like Escherichia, Helicobacter, and Salmonella are gram-negative, meaning they don’t change color with Gram stain. However, for some ...

This is because the structure of their cell wall is unable to retain the crystal violet stain so are colored only by the safranin counterstain. Examples of gram negative bacteria include enterobacter ...