Question

Identify the Gram $(-)$ bacterium

• A. Streptomyces coelicolor
• B. Escherichia coli
• C. Ampycolatopsis orientalis
• D. Bacillus subtilis

Answer 1

Answer: (B)

Escherichia coli

Gram-negative bacteria are bacteria that do not retain the crystal violet stain during gram-staining procedure. Gram positive bacteria are bacteria that retain the crystal violet stain during gram staining procedure. Examples of Gram negative bacteria include Escherichia coli, Helicobacter pylori. Examples of Gram positive bacteria include Bacillus subtilis, Streptomyces coelicolor, Streptomyces orientalis (Ampycolatopsis orientalis).

Thus, the correct answer is 'Escherichia coli.'