Microbiology- Week 5-8

    Cards (314)

    • What is the significance of cell size and surface-to-volume ratio?
      Faster nutrient uptake and more mutations
    • How are archaeal membranes different from bacterial membranes?
      Archaeal membranes are more permeable
    • What is the primary component of the bacterial cell wall?
      Peptidoglycan (murein)
    • What percentage of the cell wall in Gram-positive bacteria is peptidoglycan?
      Up to 90%
    • What drives peptidoglycan polymerization in Gram-negative bacteria?
      PBP3 and PBP2 proteins
    • What unique structure do porins consist of?
      Beta sheets forming beta barrels
    • What is the role of porins in the outer membrane?
      Allow molecules to cross to the periplasm
    • What is the large polysaccharide component of the outer membrane in Gram-negative bacteria?
      Lipopolysaccharide
    • How can bacteria be counted?
      By microscopy and culture methods
    • What is the formula for resolution in light microscopy?
      R = 0.5λ/numerical aperture
    • What is the diffraction limit of a light microscope?
      250 nm
    • What does the Gram stain exploit?
      Differences in bacterial structure
    • What are the main cell surface structures in bacteria?
      • Capsules
      • Fimbriae and pili
      • Flagella
    • What role do capsules play in bacteria?
      Pathogenesis and biofilm formation
    • What are biofilms and where do they form?
      • Predominant bacterial phenotype in nature
      • Form on solid substrates with moisture
      • Form on soft tissue surfaces in organisms
      • Form at liquid-air interfaces
    • What are fimbriae and pili made of?
      Proteinaceous structures that can be glycosylated
    • What is the function of fimbriae and pili in bacteria?
      Pathogenesis, biofilms, and conjugation
    • What is the structure of flagella in bacteria?
      Multimeric protein complex traversing membranes
    • How do flagella enable bacteria to move?
      By swimming in liquid environments
    • What percentage of the E. coli genome encodes motility-related proteins?
      Nearly 5%
    • What is the dormant stage of a bacterial lifecycle called?
      Endospores
    • What chapters in Brock cover specific stains?
      • Parts of chapters 3, 4, and 5
    • What is the focus of Lecture 5 in BIO1337?
      Antibiotics and Resistance
    • What are the intended learning outcomes (ILOs) of the lecture?
      • Knowledge of different types of antibiotics
      • Understanding modes of action of antibiotics
      • Awareness of resistance mechanisms
    • What effect do antimicrobial agents have on bacterial growth?
      They inhibit or kill bacteria
    • How is antibacterial activity measured?
      By assessing the effectiveness of antimicrobial agents
    • What are cellular structures/processes in relation to antibiotics?
      They serve as targets for antibiotic action
    • What are naturally occurring antimicrobials?
      • Antibiotics produced by microorganisms
      • Serve as "warfare" molecules
      • Examples include aminoglycosides and macrolides
    • What are aminoglycosides?
      Antibiotics containing amino sugars
    • Why are aminoglycosides considered reserve antibiotics?
      Due to neurotoxicity and nephrotoxicity
    • What do macrolides contain?
      Lactone rings bonded to sugars
    • What is the target of macrolides?
      The 50S subunit of ribosome
    • What do tetracyclines contain?
      Four rings
    • What is the medical use of tetracyclines?
      Broad-spectrum inhibition of protein synthesis
    • What are β-Lactam antibiotics?
      • Important group of antibiotics
      • Includes penicillins, cephalosporins, cephamycins
      • Over half of all antibiotics used worldwide
    • Who discovered penicillins?
      Alexander Fleming
    • What are penicillins primarily effective against?
      Gram-positive bacteria
    • How do penicillins work?
      By targeting cell wall synthesis
    • What do penicillins bind to?
      Penicillin Binding Proteins (PBPs)
    • What is the effect of penicillin binding to PBPs?
      Weakening of the peptidoglycan layer
    See similar decks