classification of pathogenic bacteria Flashcards
what are examples of gram positive cocci
staphylcocci (clusters) and streptococci and enterococci (chainns)
what is important about Coagulase-negative staphylococci
Form biofilms and may be significant pathogens in the
presence of foreign bodies/prostheses
what is Group B streptococci
Streptococcus agalactiae
Clostridium difficile
difficult to culture
important cause of the shits
Clostridium perfringens
Found in soil and normal commensal in human and animal
gut/faeces.
• Can contaminate food and cause gastroenteritis (enterotoxinproducing
strains).
Clostridium tetani
Toxin production by C. tetani cause tetanus.
• Uncontrolled muscle spasm due to loss of inhibition at neuromuscular
junction.
• Antigenically modified toxin (toxoid) used for immunisation
Clostridium botulinum
Source of “botox”
• Bacillus anthracis
– Cause of anthrax
what is 4 common gram positive bacteria
Staphylococcus aureus
• Streptococcus pyogenes
• Streptococcus pneumoniae
• Clostridium difficile
what are two common gram negative cocci
Neisseria spp
• Moraxella catarrhalis
Moraxella catarrhalis
Causative agent of respiratory tract infections.
Acid And Alcohol Fast Bacilli
Resistant to decolourisation by acid or alcohol after
staining with carbol fuchsin.
• Mycobacterium species are visualised with special
stains e.g Ziehl-Neelsen (ZN) or Auramine.
cann Leprosy be cultered
no
Spirochaetes
Long, spiral-shaped bacteria.
• Not easily visualised by light microscopy.
• Very difficult to culture (never Treponema pallidum).
• Dark ground microscopy or immunofluorescence.
• Often diagnosed by serology.
Treponema pallidum
Syphilis
