Which among the following organism can't be demonstrated by gram staining?: (A) Borrelia, (B) spirochetes, (C) Strep.pneumoniae, (D) Mycoplasma
Answer is B. Ans: b) SpirochetesBorrelia- gram negativeStrep pneumonia- gram positiveMycoplasma- gram negativeGram positive bacteria becomes gram negative when the cell wall is damaged.Even though spirochetes are grouped under gram negative organism, it is not a preferred test for diagnosing spirochetal disease.