Gram-negative bacteria are a group of bacteria that do not retain the crystal violet stain used in the Gram staining method. They have a thin peptidoglycan layer and an outer membrane containing lipopolysaccharides.
5 Must Know Facts For Your Next Test
Gram-negative bacteria are often more resistant to antibiotics due to their outer membrane.
The outer membrane of gram-negative bacteria contains endotoxins, which can cause severe reactions in humans.
Escherichia coli and Pseudomonas aeruginosa are common examples of gram-negative bacteria.
In a Gram stain test, gram-negative bacteria appear red or pink after counterstaining with safranin.
Gram-negative bacteria play significant roles in human microbiomes and environmental ecosystems.
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Related terms
Gram-positive Bacteria: Bacteria that retain the crystal violet stain and appear purple in a Gram stain test due to a thick peptidoglycan layer.
Toxins located within the bacterial cell wall, specifically found in the outer membrane of gram-negative bacteria, which can trigger strong immune responses.