list 3 people who contributed to the development of microbiology
Anton van Leeuwenhoek
Edward Jenner
Joseph Lister
Semmelweis Ignác
Louis Pasteur
Robert Koch
Paul Ehrlich
Alexander Fleming
Bacteria Shape and Size
Coccus spherical, 1µm
,Bacillus rod-shaped, 5-10µm Spirochetes
spiral, 20-30µm
what are the most frequently used basic culture media?
Nutrient agar
blood agar
chocolate agar
what are the most frequently used selective culture media?
Eosin-methyleneblue culture medium (EMB)
Bismuth-sulphite agar
Clauberg agar
Lowenstein-Jensen medium
Obligate Structures of Bacterial Cell
Nucleoid, ribosome, and cytoplasm, plasma membrane, outer membrane
(periplasmic space for G- bacteria)
Optional Structures of Bacterial Cell Capsule,
pilus, and cilia, spore, plasmid
,what are the 4 steps of the Replication Curve of Bacteria?
Lag phase, log phase, stationary phase, and decline phase
How long does it take for an average bacterium to form colonies on agar plates? overnight,
taking 16-18 hours
what does sterilization mean?
Complete elimination or destruction of all forms of microbial life
What does disinfection mean?
Reduction of the number of microbes to prevent infections.
Parameters Influencing effectivity of Sterilization (3 examples)
- number of germs
- resistance of germs
- concentration of disinfectants
- presence of organic materials
- the initial time
- presence of biofilm
what are the parameters for hot air sterilisation?
Sterilization at 180°C for 1 hour, 160°C for 2 hours, or 140°C for 3 hours.
, parameters of the Autoclaving Process +1
atm overpressure, 121°C for 20-30 minutes
or 134°C for 10 minutes at 2tms overpressure
list chemical agents used for gas sterilisation
Ethylene oxide
formaldehyde beta-
propriolactone
what is the theoretical background of plasma sterilisation?
Hydrogen peroxide in high electric field turns into plasma state, the produced free radicals kill microbes
Bacterial Cell Surface Antigens
O-antigen (cell wall), H-antigen (flagella), and K-antigen (capsule) are important for identification.
what does agglutination mean?
Serological reaction in which binding of cellular sized antigens (RBCs or bacterium cell) and their specific
antibodies results in clumping