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58 Cards in this Set
- Front
- Back
- 3rd side (hint)
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What is the function of bacterial Peptidoglycan?
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Gives rigid support, protcts agains osmotic pressure.
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p. 130
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What is the chemical composition of bacterial peptidoglycan
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Sugar backbone with cross-linked peptide side chains.
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p. 130
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What is the function of bacterial Cell wall/cell membrane (gram +)?
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Major surface antigen
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p. 130
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What is the chemical composition of bacterial Cell wall/cell membrane (gram +)? What does it induce?
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Teichoic acid induces TNF and IL-1
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p. 130
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What is the function of bacterial Outer membrane (gram -)?
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Site of endotoxin (lipopolysaccharide); major surface antigen
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p. 130
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What is the chemical composition of bacterial Outer membrane (gram -)? What does it induce? What is the antigen?
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Lipid A induces TNF and IL-1; polysaccaride is the antigen.
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p. 130
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What is the function of bacterial Plasma membrane?
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Site of oxidative and transport enzymes.
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p. 130
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What is the chemical composition of bacterial Plasma membrane?
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Lipoprotien bilayer
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p. 130
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What is the function of bacterial Ribosome?
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Protein synthesis
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p. 130
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What is the chemical composition of bacterial Ribosome?
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RNA and protein in 50S and 30S subunits
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p. 130
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What is the function of bacterial periplasm?
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Sapce between the cytoplasmic membrane and outer membrane in gram-nagative bacteria.
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p. 130
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What is the chemical composition of bacterial periplasm?
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Contains many hydrolytic enzymes, incuding beta-lactamases.
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p. 130
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What is the function of bacterial capsule?
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Protects agains phagocytosis
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p. 130
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What is the chemical composition bacterial capsule? What bacteria is the exception and how?
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Polysaccharide (except Bacillus enthracis, which contains D-glutamate)
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p. 130
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What is the function of bacterial Pilus/fimbria
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Mediates adherence of bacteria to cell surface; sex pilus forms atttachement between 2 bacteria during conjugation
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p. 130
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What is the chemical composition of bacterial pilus/fimbria?
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Glycoprotein
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p. 130
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What is the function of bacterial Flagellum?
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Motility
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p. 130
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What is the chemical composition of bacterial flagellum?
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Protein
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p. 130
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What is the function of bacterial Spore?
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Provides resistance to dehydration, heat, and chemicals.
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p. 130
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What is the chemical composition of bacterial spore?
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keratin like coat; dipicolinic acid
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p. 130
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What is the function of bacterial Plasmid?
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Contains a variety of genes for antibiotic resistance, enzymes, and toxins.
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p. 130
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What is the chemical composition of bacterial Plasmid?
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DNA
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p. 130
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What is the function of bacterial Glycocalyx
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Mediates adherence to surfaces, especially foreign surfaces (indwelling catheters).
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p. 130
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What is the chemical composition of bacterial flagellum?
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Polysaccharide
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p. 130
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What part of the cell wall is unique to gram positive organisms?
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Teichoic acid
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p. 130
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What 5 elements of bacterial cell wall and outer structures are common to both gram + and gram - bacteria?
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flagella, pillus, capsule, peptigoglycan, cytoplasmic membrane.
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p. 130
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What part of the cell wall is unique to gram negative organisms?
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Endotoxin/LPS (outer membrane)
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p. 130
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How do the peptidoglycan layers of gram + and - bacteria compare?
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Gram positives have much thicker peptidoglycan layers than gram negatives.
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p. 130
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What does the lag phase represent in the bacterial growth curve?
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lag - metabolic activity w/o division
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p. 131
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What does the log phase represent in the bacterial growth curve?
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log - rapid division.
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p. 131
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What does the stationary phase represent in the bacterial growth curve?
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stationary - nutrient depletion slows growth
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p. 131
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What does the death phase represent in the bacterial growth curve?
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death - prolongued nutrient depletion and build up of waste products lead to death
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p. 131
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What are the 4 phases of the bacterial growth curve?
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lag, log, stationary, death
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p. 131
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What is the source of EXOtoxin?
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Certain species of SOME gram + and - bacteria
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p. 131
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What is the source of ENDOtoxin?
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Cell wall of MOST gram - bacteria and LISTERIA
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p. 131
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What is the fate of ENDO toxin?
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It is kept on the cell
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p. 131
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What is the fate of EXOtoxin?
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It is secreted from the cell
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p. 131
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What is the chemistry of EXOtoxin?
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Polypeptide
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p. 131
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What is the chemistry of ENDOtoxin?
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Lipopolysaccharide
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p. 131
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Where is the EXOtoxin gene located?
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Plasmid or bacteriophage
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p. 131
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Where is the ENDOtoxin gene located?
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Bacterial chromosome
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p. 131
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What is the level of toxicity of EXOtoxin?
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High (fatal dose on the order of 1 micro-gram)
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p. 131
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What is the level of toxicity of ENDOtoxin?
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Low (fatal dose on the order of hundreds of micrograms)
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p. 131
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What are the 2 clinical effects of ENDOtoxin?
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Fever, shock
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p. 131
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What is the mode of action of ENDOtoxin?
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Includes TNF and IL-1
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p. 131
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Describe the antigenicity of EXOtoxin.
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Induces high-titer antibodies called antitoxins
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p. 131
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Describe the antigenicity of ENDOtoxin
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Poorly antigenic
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p. 131
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Describe the vaccine for EXOtoxin?
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Toxoids used as vaccines
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p. 131
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Describe the vaccine for ENDOtoxin?
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No toxiods formed, no vaccine available.
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p. 131
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What is the heat stability of EXOtoxin? What is the exception?
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Destroyed rapidly at 60C (except staphylococcal enterotoxin)
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p. 131
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What is the heat stability of ENDOtoxin?
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Stable at 100C for 1hour.
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p. 131
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Name 3 disease that have EXOtoxins.
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Tetanus, botulism, diphtheria
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p. 131
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Name 2 disease that have ENDOtoxins
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Meningococcemia, sepsis by gram - rods
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p. 131
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What type of exotoxins bind directly to MHC II and T-cell receptor, activating large numbers of T cells to stimulate release of IL-1 and IL-2?
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Superantigens
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p. 132
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What is the mechanism of action of superantigens?
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Bind directly to MHC II and T-cell receptor, activating large numbers of T cells to stimulate release of IL-1 and IL-2?
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p. 132
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Name 2 bacteria that release exotoxins that are superantigens?
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S. aureus and S. pyogenes
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p. 132
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What are the 2 enterotoxins of S. aureus and what are their effects?
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1. TSST-1 causes toxic shock syndrome (fever, rash, shock). 2. Enterotoxins cause food poisoning.
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p. 132
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What is the enterotoxin of S. pyogenes adn what does it cause?
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Secarlet fever - strain SPE toxin causes toxic shock-like syndrome.
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p. 132
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