Biofilm Flashcards
How does P. aeurginosa attack CF patients?
biofilm is able to build in CF patients’ mucus more
can survive in anaerobic lung conditions
Colonization
body is never able to clear the infection
infection becomes part of your flora
MIC
mean inhibitory concentration
lowest concentration of a drug needed to prevent bacterial cell growth
example of drug tolerance
biofilms prevent the drug from reaching the target bacteria
difference between drug resistance and tolerance
resistance: genetic code inactivates or expels drug *can be innate or acquired
tolerance: environmental factors prevent drug from working
innate drug resistance
selective pressure keeps only population with a beneficial mutation around
acquired drug resistance
bacteria share genes through conjugation
transposons in plasmids get shared through conjugation
What is a biofilm?
aggregate bacterial lifestyle
can have different types of bacteria in the same community
the bacteria live in a suspended polysaccharide film that they create
What class of drugs is clositin?
Polymyxins
How do Polymyxins work?
bind LPS on gram neg. bacteria and disrupt the cell membrane
What class of drugs is meropenem?
B-lactam antibiotic
How do B-lactam antiboitics work?
inhibit bacterial cell wall production by blocking peptidoglycan synthesis
Staphylococcus epidermidis
gram positive cocci that normally lives on skin surface
How can resistance / tolerance (4) occur
biofilm can prevent drug from reaching target bacteria
bacteria pumps the drug out
mutations in the bacterial site we are trying to target
if colonized bacteria aren’t actively dividing, then the drug is not working
What class of drugs is aztreonam?
B-lactam antibiotics
