Lecture 23 Flashcards
Microbial Chemical Warfare (17 cards)
Antibiotics
for bodily surfaces.
treat bacterial infections
penicillin’s mechanism
inhibiting peptidoglycan synthesis
this makes it an exceptional antibiotic because normal human cells dont have peptidoglycan
where does penicillin come from
moldy cantaloupe! its a fungi (heterotroph)
where does streptomycin come from
a soil bacterium (actinomycete)
soil
an arena for microbial competition.
it is a very nutrient-rich environment
many orgs doing same thing, living in close contact
… this encourages the production of complex antibiotics to compete with one another
colicin
protein that has toxic effects on certain e. coli strands.
how was penicillin discovered
bacteria unable to grow around mould
broad-spectrum antibiotics
kill many microbes.
may lead to superinfections
can unintentionally leave drug-resistant pathogens behind without competition to proliferate
disturbance
resetting community
urgent threat to gut microbiome after a disturbance
c. diff
- spore forming, toxin producing
c. diff treatment
transplant of fecal microbiome
where does resistance come from
bacteria develop mutations after frequent exposure to antibiotics
isolated people still showing antimicrobial resistance
due to natural competitive processes (this is because antimicrobial compounds are almost all natural)
MIC
min. inhibitory concentration
correct dose
why do microbes produce these compounds in way lower quantities in nature?
large carbon cost
resistant cheaters can get a free ride when a lot is produced
subclinical conc.s already reduce the growth rates of competitors - dont need more
potential ecological role of toxins
kind of opposite of antibiotics
organisms have complex gut microbiomes … toxins kill some eukaryote cells - some which are predators to healthy essential bacteria
antiretroviral therapy (ART)
