The Bacteria I Flashcards
(36 cards)
Bacteriophage
- Bacterial virus that results in death of bacteria.
- Incorporates DNA into bacterial genome
Flagella
- Long, helical structures extending from bacteria that allow bacteria to move in environment.
- Built by highly antigenic proteins
Pili
- More rigid extensions from bacteria
- Involved in attachment to host cells or other bacteria
Gram Stain
- Method to differentiate between bacteria on the basis of the thickness of their cells walls
- Usually the first test done for identification
Gram Stain Procedure
- Fixation
- Crystal Violet
- Iodine (cross link crystal violet so it gets stuck in G+ bacteria)
- Decolorization (crystal violet washed out from G- bacteria)
- Safranin (stains G- bacteria)
Endospores
- Some bacteria can form endospores in response to environmental stressors
- Allows them to survive for many years without actively growing
- Highly resistant to disinfection and killing by other methods
- Abundant in soils
- eg. Clostridial species, Bacillus anthracis
Bacterial growth and division
-Depends on nutritional status in environment and type of bacteria
Bacterial Growth Curve Phases
- Lag Phase
- Exponential (Logarithmic) Phase
- Stationary Phase
- Death Phase
Staphylococcus aureus
- G+
- Aerobic
- Catalase +
- Cocci in clusters
- P: TSST, Enterotoxin
- CS: SSTI, Necrotizing fasciitis, Endocarditis, Osteomyelitis
Coagulase Negative Staphylococcus
- eg. S. epidermidis
- G+
- Aerobic
- Catalase +
- Cocci in clusters
- P: Biofilm production
- CS: Nosocomial blood stream infections, prosthetic material infections
Group A Streptococcus
- eg. S. pyogenes
- G+
- Aerobic
- Cocci in pairs/chains
- Catalase -
- Beta hemolytic
- P: Streptolysin O&S
- CS: Pharyngitis, Necrotizing Fasciitis, Rheumatic Fever
Group B Streptococcus
- eg. S. agalactiae
- G+
- Aerobic
- cocci in chains/pairs
- Catalase -
- beta hemolytic
- P: polysaccharide capsule
- CS: neonatal diseases (meningitis, sepsis, pneumonia)
Streptococcus pneumoniae
- G+
- Aerobic
- Catalase -
- alpha hemolytic
- cocci in pairs/chains
- P: polysaccharide capsule
- CS: CAP, otitis media, conjunctivitis, meningitis
Strep mitis
- G+
- Aerobic
- cocci in pairs/chains
- alpha hemolytic
- catalase -
- P: polysaccharide capsule
- CS: Bacteremia, endocarditis
Enterococci
- G+
- Aerobic
- cocci in pairs/chains
- non hemolytic
- catalase -
- P: surface adhesins
- CS: nosocomial VRE, UTI’s, endocarditis
Corynebacterium diphtheriae
- G+
- non-branching rods
- Aerobic
- Catalase +
- P: diphtheria toxin
- CS: pharyngeal diphtheria
Corynebacterium jeikeium
- G+
- Aerobic
- non branching bacilli
- Catalase +
- CS: foreign body ix’s
Listeria monocytogenes
- G+
- Aerobic
- bacilli
- motile
- Catalase +
- P: hemolysin
- CS: gastroenteritis, meningitis, stillbirth and preterm labor in pregnancy
Peptostreptococcus
-G+
-Anaerobic
-elongated cocci
CS: pelvic ix’s, cutaneous, respiratory ix’s
Actinomyces israelii
- G+
- Anaerobic
- Bacilli
- CS: Oral/cervicofacial ix’s, pelvic ix’s
Clostridium tetani
- G+
- Anaerobic
- Bacilli
- Sporulating
- P: Tetanus toxin
- CS: Tetanus
Clostridium perfringens
- G+
- Anaerobic
- Bacilli
- Sporulating
- P: alpha toxin, enterotoxin
- CS: Gas gangrene, acute necrotizing GI ix
Clostridium botulinum
- G+
- Anaerobic
- Sporulating
- Bacilli
- P: Botox toxin
- CS: Botulism (flaccid paralysis)
Clostridium difficile
- G+
- Anaerobic
- Bacilli
- Sporulating
- P: Toxin A&B
- CS: abx associated diarrhea