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Lectures 45,46: Bacteria-Structure & Physiology - Coggle Diagram

- - - - extreme acidophiles
        acidophiles
        neutrophiles
        alkalophiles
        extreme alkalophiles
    - - directly related to enzyme activity
      - mesophiles:**bacteria that affect humans (~15-45 degrees C)
    - - TO BE Aerobic:
        need catalase (digest H2O2) &
        superoxide dysmutase (to digest superoxidase)
      - Strict anaerobes (clostridia)
      - Aerotolerant anaerobes (fermenters)
      - Microaerophiles (i.e., H. Pylori or Neisseria)
      - Facultative aerobes (i.e., E. Coli)
      - Strict aerobes (i.e., bacillus)
  - - - in ALL bacteria except Myocoplasma
        
        Mycoplasma- acid-fast staining used! :!:
        
        Ziehl-Neelsen Stain :star:
        
        Carbofuschin into impermeable cell
        needs a LOT of heat, dye, experience
        no longer used
        
        Auramine-Rhodamine Stain :star:
        
        Faster, less time + experience
        Lower magnification
        but NEED fluorescent scope
      - Function: Protect from osmotic pressure
      - Useful- gram stain identification
        
        stains Peptidoglycan layer
        
        Positive= Purple!
        
        Thick(up to 30 layers)
        Holds Crystal violet well
        
        Negative= Pink!
        
        Thin (single layer)
        doesn't hold crystal violent well
        counterstain w/Safarin!
        
        Bacteria that DO NOT Stain Well! :red_cross:
        
        Mycobacteria (+)
        Treponema (-)
        Legionella
        Rickettsia
        Chlamydia (-)
        Bartonella (-)
        Ehrlichia (-)
        Anaplasma (-)
        Mycoplasma (no cell wall)
        
        differentiates +/-, morphology, & pattern
        
        GRAM STAIN Sequence :star:
        
        Crystal Violent
        
        Gram's iodine
        
        Ethanol (decolorize)
        
        Safarin (counterstain)
      - NAG-NAM Glycan Chains- connected by tetrapeptide chains &
        peptide interbridge (in + cells) OR
        covalent bonds (-) cells
        :explode:
    - - 4 Functions :red_flag:
        
        Attachment
        
        Complement system (avoid)
        
        Biofilm formation
        
        Resist Antibody neutralization
        
        Resist phagocytosis
    - - used- longevity when essential nutrients missing (dormant stage)
        
        Viable (still alive)
        
        Metabolically dormant (avoid antibiotic activity)
        
        Highly Resistant
        (killed by autoclave or long boil)
        
        Chemical protection:
        (spore wall/cortex/exosporium)
        
        UV damage protection
        (small acid soluble proteins SASPs
        
        (1) binds to DNA --> "A" conformation
        
        (2) all radiation damage makes "spore photoproduct" thymine dimers
        
        (3) cell vegetative again- has enzyme now to fix damage!
        
        Dry conditions
        Dipicolinic acid (DPA)
        
        terminal (end of cell)
        or
        internal (middle)
      - BACILLUS (aeorobic)
        
        (1) B. anthracis
        (anthrax disease)
        -cutaneous, GI, inhalation
        
        (2) B. cereus
        (causes food poisoning)
      - CLOSTRIDIA (STRICT anaerobes)
        
        C. botulinum
        flaccid paralysis
        
        improper canning
        honey- infants
        blocks ACh at CNS
        
        C. tetani
        tetanic paralysis
        
        blocks ACh at NMJ
        
        C. perfingens
        (gas gangrene)
        
        C. difficile
        (C-Diff- deadly diarrhea)
        
        normal in gut flora
        overgrowth cause: overuse of antibiotics
    - - Only in Gram neg bacteria
      - Can cause Septic shock
        
        3 parts:
        
        Lipid A
        
        Oligosacc core
        
        O-specific antigen
        
        Lipid A activates up to 1% lymphocyte population
        
        catastrophic immune response
        TLR4 (macrophage) activated
        complement activation
        tissue factor activation
        (leads to coagulation and DIC)
- - - - Donor cells connect to recipient via conjugation pilus
        
        Extrachromosomal plasmid transferred
        
        1 strand transferred!
        Recipient makes complementary strand
    - - common in Neisseria, S. Pneumoniae, H. Influenzae
        
        Donor cell takes up "naked" donor DNA
        Recombination
        incorporated into chromosomal DNA
    - - Generalized
        Specialized
        
        Bacteriophage infects host cell
        Incorporates host DNA into viral DNA
        Phage infects new cell &
        DNA from cell 1 --> 2nd cell
        New recombinant cell made