Chapter 2: Gram+ and Gram- Bacteria Flashcards
Postive or Negative?
Gram-Positive
Gram-Positive Bacteria Stain Color
Blue/purple
Gram-Negative Bacteria Stain Color
Pink/red
Peptidoglycan
The primary structure of the cell wall; repeating sugars of N-acetyl glucosamine (NAG) N-acetyl muramic acid (NAM)
Teichoic Acid
polymers of glycerol or ribitol joined by phosphate groups; in the cell wall
Wall teichoic acids
go part way through the wall; protrudes above the wall; gram-positive
Lipoteichoic acids
go completely through the wall and link to the plasma membrane; protrudes above the wall; gram-positive
M Protein
a virulence factor; it protrudes from the cell wall; it is required for infection; it is highly susceptible to mutations; gram-positive
Mycolic Acid
found in myobacterium; waxy liquid incorporated into cell wall; makes cell extremely resistant to environmental stress; acts as a barrier against antibiotics & host defenses; gram-positive
Periplasmic Space
between plasma and cell wall; smaller in gram-positive
Exoenzymes
Enzymes secreted by gram-positive bacteria that inflict damage on host’s tissues
Unique Features of Gram-Positive Wall
Thick peptidoglycan; Phospholipid molecules; one membrane; Teichoic acid & lipoteichoic acid
lipopolysaccharides
compose the outer membrane of Gram-Negative wall; act as a barrier
Phospholipid Molecules
compose the outer wall of the Gram-Positive bacterium
Teichoic Acids - present or not present in Gram-negative and Gram-positive?
Gram-negative: absent
Gram-positive: present
Name differences between Gram-Positive and Gram-Negative: Peptidoglycan, Teichoic Acid, Lipids, Outer membrane, Toxins, Sensativity to Antibiotics
