Test 3 Chapter 14 Study Guide Flashcards
Paul Ehrlich
Early 1900s. Searched for the magic bullet
Magic bullet
Something that would kill a microbe but be safe for the host
Salvarsan
Can treat syphilis
Klarer, Mietzsch and Domagk
Discovered antimicrobial properties of the dye, Prontosil
Domagk
Continued work with antimicrobials. Worked with sulfanilamide that would become the first synthetic anitmicrobial.
Alexander Fleming
“accidentally” discovered penicillin.
Penicillin discovery
Alexander Fleming was growing Staphylococcus aureus. Went on vacation, petri dishes left up. Fungal growth occurd. Aureus died on plates with fungi.
Dorothy Hodgkin
Discovered structure of penicillin leading the way for semi-synthetic antimicrobials.
Selman Waksman
Discovered several antimicrobials isolated from fungi and Streptomyces spp.
Selective toxicity
chemical agent or drug can exert a toxic effect on a pathogen and leave the infected host organism unharmed.
Narrow-Spectrum anitmicrobial
Hits a few things. targets a specific group of bacteria. I.E. Gram-positive bacteria
Broad-Spectrum antimicrobial
Hits lots of things. Would target Gram-Positive and Gram-Negative bacteria for example
Broad-Spectrum antimicrobial and super infections
An opportunistic pathogen might take over the treated biome as good bacteria was destroyed by the broad spectrum antimicrobial
Super infection
A secondary infection that occurs in an individual who is already infected with another strain of the same virus or bacteria.
Enteral Route
Orally
Parenteral Route
injection - fastest plasma concentration
Synergistic Drug Interactions
Drugs do good things when taken together
trimethoprim and sulfamethoxazole
Block different steps in the folic acid production metabolic pathway in bacteria. Allows a larger population of bacteria to be neutralized
Antagonistic Drug Interactions
Drugs negatively impact one another
Antagonistic Drug Interactions - Example
Antacid use with some antimicrobials.
Antimicrobials and birth control. Antimicrobial reduces efficacy of birth control
penicillin mechanism
Beta lactam - naturally occuring.
Inhibits cell wall biosynthesis
Narrow Spectrum - Gram positive bacteria
cephalosporins mechanism
Beta Lactam - naturally occurring
Inhibits cell wall biosynthesis
Narrow Spectrum - Gram positive bacteria
vancomycin mechanism
Inhibits cell wall biosynthesis
Narrow Spectrum - Gram positive bacteria
offspring of penicillin - synthetic though
bacitracin mechanism
Inhibits cell wall biosynthesis
Narrow Spectrum - Gram positive bacteria
Triple antibiotic ointment
aminoglycosides Mechanism
Inhibitor of protein biosynthesis - targets ribosomes
Broad Spectrum
neomycin - Triple antibiotic ointment
tetracycline mechanism
Inhibitor of protein biosynthesis
targets ribosomes
Broad Spectrum
azithromycin mechanism
Inhibitor of protein biosynthesis
Targets ribosomes
Broad Spectrum
chloramphenicol mechanism
Inhibitor of protein biosynthesis
targets ribosomes
Broad Spectrum
Very low cost, very targeted, easy to give.
chloramphenicol why don’t we use it more?
can cause aplastic anemia, so we don’t give it unless we have to
polymyxin B
triple antibiotic ointment
Inhibitor of membrane function
dapsone
hansen’s diseases - Hep C
Inhibitor of membrane function
metronidazole
really broad spectrum
Inhibitor of Nucleic Acid Synthesis
Bacteria and protist
rifampin
one of the first drugs used for tuberculosis
Inhibitor of Nucleic Acid Synthesis
fluoroquinolones
Inhibitor of Nucleic Acid Synthesis
Ciprofloxacin, poxin
sulfonamides
folic acid pathway
Inhibitors of Metabolic Pathways
trimethoprim
folic acid pathway
Inhibitors of Metabolic Pathways
isoniazid
first line of tuberculosis therapy
Inhibitors of Metabolic Pathways
fluconazole
Targets ergosterol. Sterle in fungal plasma membranes. Very targeted
quinolones
antiprotozoal drug
treatment for maleria
ivermectin
Anthelmintic drug
affects nervous system
praziquantel
Anthelmintic drug
affects nervous system
acyclovir
used to fight herpes
Antiviral Drug
Found in Triple antibiotic ointment
Bacitracin, Neomycin, Polymyxin B
Mechanisms of Drug Resistance
How does a bacteria make it self unresponsive to a anti-microbial
Efflux Pump
Active removal of the antimicrobial from the microbe. It gets in then pumped out.
Blocked Penetration
Antimicrobial isn’t let in.
Target modification
Bacteria change the shape of the target of the antimicrobial. Reduces the effectiveness of antimicrobial
Inactivation of enzymes
Produces something that breaks down the antimicrobial destroying it.
Target Mimicry
Bacteria produce something that looks like the target of the drug but does nothing. Decoy.
Multidrug-resistance microbes (MDRs)
“superbugs”
one or more resistance mechanisms
Cross Resistance
Single resistance mechanism inactivates multiple antimicrobials.
MRSA
Semisynthetic penicillin designed to target penicillin resistant S. Aureus
VRSA
Vancomycin-Resistant Enterococci and Staphylococcus Aureus
Narrow Specrtum antimicrobial
One of the last lines of defense for MRSA
MDR-TB
Multidrug-resistant mycobacterium tuberculosis
resistant to first line of defense
XDR-TB
Extremely drug resistant tuberculosis. we have nothing to treat these.
