Bacterial culture (midterm) Flashcards
What are examples of bacteria that cannot be cultured in vitro?
Chlamydia
Rickettsia
Mycobacterium leprae
Treponema pallidum
What conditions do Chlamydia and Rickettsia need?
Tissue culture
What conditions do Mycobacterium leprae and Treponema pallidum need?
Animal infection
What are the types of simple media?
Nutrient broth
Nutrient agar
What are the components of nutrient broth?
Peptone
Meat extract
NaCl
What are the components of nutrient agar?
Nutrient broth (peptone, meat extract, NaCl)
2% agar
What are the types of special media?
Enriched media
Differential media
Selective media
Transport media
Anaerobic media
What are the types of enriched media?
Blood agar
Chocolate agar
What characteristic of bacteria necessitates enriched media?
Fastidious/exacting bacteria
What are the components of blood agar?
Nutrient agar
Mammalian blood (usually horse or sheep) at 5–10%
What are the components of chocolate agar?
Blood agar slowly heated to 80ºC causing hemolysis
What is an example of a bacterium requiring chocolate agar?
Haemophilus influenzae
What are the typical constituents of selective media?
Antibiotics
Dyes
Chemicals
Specific pH
What are the components of Thayer–Martin medium?
Vancomycin: kills G+ bacteria
Colistin: kills most G– bacteria
Nystatin: kills most fungi
Trimethoprim: inhibits most G– negative bacteria, especially swarming Proteus
What bacteria is selected for by Thayer–Martin medium?
Neisseria gonorrhoeae
What is the function of vancomycin in Thayer–Martin medium?
Kills G+ bacteria
What is the function of colistin in Thayer–Martin medium?
Kills most G– bacteria (except N. gonorrhoeae)
What is the function of nystatin in Thayer–Martin medium?
Kills most fungi
What is the function of trimethoprim in Thayer–Martin medium?
Inhibits G– bacteria, especially swarming Proteus