Gram-Positive Bacteria Hedy Wang 10D

Characteristics Has a thick, multilayered cell wall consisting mainly of peptidoglycan surrounding the cytoplasmic membrane. Retains crystal violet dye and stains dark violet or purple; Remains coloured blue or purple with gram stain when washed with absolute alcohol and water. Have teichoic acids in cell membrane

Examples Streptococcus pneumoniae Bacillus anthracis Pneumonia, meningitis Bacillus anthracis Anthrax

Gram Positive VS. Gram Negative Have similar internal, but very different external structures. On adding a counterstain such as safranin or fuchsine after washing, Gram-negative bacteria are stained red or pink while Gram-positive bacteria retain their crystal violet dye.