1. Temperature Adaptation Flashcards
Which two broad qualities of pathogenic bacteria allow them to cause disease?
- Invasiveness
2. Ability to produce toxins
What is the difference between exotoxins and endotoxins?
Exotoxins are released from bacterial cells
Endotoxins are cell associated substances that are structural components of the cell walls of Gram + bacteria
Which gastrointestinal pathogens have an environmental source?
Campylobacter, Salmonella, Shigella
What is a psychrophile’s min, opt, max temp
below 0
10-15
below 20
What is a mesophile’s min, opt, max temp
10-15
30-40
below 45
What is a psychrotroph’s min, opt, max temp
0
15-30
above 25
What is a thermophile’s min, opt, max temp
45
45-70
above 100
What occurs in E.coli after a decrease in T?
inhibition of most protein synthesis, acclimation phase occurs and cold shock proteins are induced
Name three examples of Class I cold shock proteins and what they do
Csp A - RNA chaperone
Csp D/G - RNA/DNA chaperones
Csd A - 70 kDa ribosome associated activity
Nus A - termination and anti termination
Name three examples of Class II cold shock proteins and what they do
Rec A - recombination factor
Gyr A - subunit of topoisomerase DNA gyrase
IF-2 - initiation factor
At what range of temperatures does Listeria grow?
4-40
Who is listeria a danger to?
Pregnant women - can fall ill and baby can die or be premature
Immunocompromised
What virulence factors does listeria use for the invasion of mammalian cells?
Internalin A and B
What virulence factors does listeria use for escape from a vacuole?
LLO - pore forming cytotoxin
PlcA - removes charged heads from phospholipids
What virulence factors does listeria use for movement through the cytoplasm and cell-cell spread?
ActA - interacts with host cell proteins to stimulate actin polymerisation
