Lecture 6: dao Flashcards
what can biofilms cause in dentistry
peridontal disease
what can biofilms cause in microbial engineering
-biofouling, waste water treatment and biomediatiopm
biofilms cause over… of hospital aquired infections
65%
where are biofilms in hospitals:
medical devices, catheters and implants
what can biofilms cause in a heart valve
endocarditis
true or false: biofilms can cause biofilms
true
biofilms in people are due to….
chronic pr subacute infections
what are the 6 main points in biofilms
-multicellular bacterial communities
-extracellular matrix (glue that binds it all)
-non-motile cells attached to a surface or to each other
-physiologic heterogeneity (all bacteria will differenciate a tad from everyone else)
-bacterial communication
-specialized subpopulations
where is b subtilis from?
-soil organism and gut commensal
which bacteria is a potential beneficial bacteria for plants
b subtilis
true ot false: b subtilis is a poor biofilm former
false it is a good one
staphylococcus aureus is a major pathogen of the ……
skin, soft tissue and foreign body infections
staph aureus is highly adherent to what
to abiotic and mucosal surfaces
true or false: staph aureus is a foreign body expert
true
pseudomonas aeruginosa is an important …. pathogen
fibrosis
which bacteria causes lethal infection
peudomonas aeruginosas it forms complex biofilm structures
where is pseudomonas aeruginosas found
in the environment
true or false: e.coli is an uti pathogen
true
Which statements are true about biofilms? select ALL that apply
* biofilm growth requires a few specific genes that are rare among pathogens
* biofilm cells behave differently from planktonic bacteria
* antibiotics are made by bacteria growing as biofilms
* biofilm cells are less susceptible to antibiotics and immune defenses
* all of you have touched biofilms with your fingers
- biofilm cells behave differently from planktonic bacteria
- biofilm cells are less susceptible to antibiotics and immune defenses
- all of you have touched biofilms with your fingers
Abiotic adherent biofilms
- Calgary device, 96-well plates, Biofilm adherent to polystyrene surface
- Growth under static conditions
- Quantification of biofilm biomass after staining with crystal violet
- Easy, high throughput
- Limited biomass and architecture, highly attachment dependent
pedicle biofilms
- auto-aggregated cell clusters, typically at the air-liquid interface
- Bacterial are mostly adherent to each other, with a few adherent to side surfaces
- Easy, but poorly quantitative
- Few species (B. subtilis) develop structured biofilms
in vitro biofilm models: flow cell biofilms
- Flow cell chambers
- Visualization by confocal microscopy
- Under continuous flow (shear stress)
- Complex biofilm architecture
- Low throughput and complex
in vitro biofilm models: microcolony or gel biofilms
- Under static conditions in semi-solid media
- Bacteria are primarily adherent to each other
- Simple, reproducible and quantitative
- Colony biofilms on agar or membranes
- Limited imaging
- Complex architecture in some species, strains and conditions
biofilm devlopment
-initial attachment
-irreversible attachment and cell replication
-early biofilm formation
-biofilm maturation
-biofilm dispersal
