Bacterial Metabolism Flashcards
What is the difference between the bacterial ribosome and the euk ribosome?
Bacterial is 70S and Euk is 80S
How is reproduction limited in bacteria vs. euks?
In bacteria it is based on genetic relatedness and similar function and in euks there are sharp species boundaries defined by fertile offspring.
How do bacteria reproduce?
by binary fission
How is PCR most useful in molecular diagnosis of bacteria?
What is an example of this?
It is used to identify slow growing or non-cultivatible bacteria.
C.diff identification
How is RFLP useful in molecular diagnosis of bacteria?
It is used to determine the source of an infection. Detection between similarities and differences between fragments of patient and hospital personnel.
What do the folowing labels mean?
- Obligate aerobe
- Microaerophile
- Facultative anaerobe
- Aerotolerant
- Obligate anaerobe
- Metabolize O2, needs it present
- Metabolize O2 only in low O2 environment
- Can respirate or ferment
- Only ferments, ignores O2
- Doesn’t grow in presence of O2
What form does potential energy remain in for fermenting bacteria?
Lactic acid
What does diagnostic fermentation mean?
It gives a specific bacteria and advantage in the environment.
What is the terminal electron acceptor in fermentation?
Pyruvate
What is the Oxidase test?
Aerobes turn indicator blue using Cytochrome C.
Facultative aerobes use Cytochrom D and have little response to oxidase test.
How does the mixed acid/butanediol fermentations work?
Which acid is converted to gas?
Grow bacteria anerobically in sugar and score for acid (yellow) and gas. Stronger anerobes produce more gas and more acid in the form of lactate.
Formate is converted to CO2
What does each stage of the bacterial growth curve mean?
Lag-
Exponential-
Stationary-
Death-
Lag - No cell division: adaptation and increased metabolism
Exponential - Balanced significant growth
Stationary - Decreased nutrients, change in pH, build up of toxic products
Death - Eventual, slope varies with species
Most bacteria that cause human disease and operate within the range of human temperatures are termed what? What is their temperature range?
Mesophilic - 10C to 40C
What is Mannitol salt media 7.5% NaCL used for?
It selects for Gram positive by inhibiting gram negative growth
