Definitions/G+/G- Flashcards
Gram + bacteria have
a thick peptidoglycan cell wall
stain purple on gram stain
G-ve bacteria have
thin peptidoglycan
pink gram stain
lipopolysaccharide outer membrane
periplasmic space
Gram negatives are harder to treat with antibiotics because
they cannot cross the double membrane
LPS is also toxic
the LPS is made up of
lipid A outer membrane
core polysaccharide
O polysaccharide inner membrane
the structure of the LPS varies due to
environmental stimuli
definition of pathogenicity
the ability to cause disease in the host
definition of virulence
quantitative measure of the ability of a pathogen to cause disease
duration, dose and severity
definition of a virulence factor
enable a bacterium to replicate and disseminate within a host in part by subverting or eluding host defences
examples of virulence factors
- secreted products
- surface proteins
- iron aquisition proteins
- flagella
- adhesins
- LPS
- endotoxins
- capsule
- pili
- secretion systems
